Method of processing non-real time service and broadcast receiver

ABSTRACT

A method of processing a non-real time service of a broadcast receiver, which receives and processes a service being transmitted in non-real time, and a broadcast receiver are disclosed. Herein, the method of processing a non-real time service of a broadcast receiver includes receiving a signaling information table including additional information on contents configuring a non-real time service and a content identifier for each content, acquiring and storing the additional information on contents and the content identifier for each content from the signaling information table, when a non-real time specific service guide is requested from a real-time specific service guide screen, configuring the non-real time specific service guide based upon the stored additional information and content identifier of the stored contents, thereby displaying a non-real time specific service guide screen, and performing a playback or download scheduling function on the content selected from the non-real time specific service guide screen.

BACKGROUND OF THE INVENTION

1. The field

The present disclosure relates to a method for processing non-real timeservice and broadcast receiver thereof.

2. Description of the Related Art

A digital television (DTV) can not only provide video and audio serviceswhich are conventional TV services, but can now also provide variousother services. For example, the DTV can provide an Electronic ProgramGuide (EPG) or the like to the user and can simultaneously providebroadcast services received through 2 or more channels. Especially, thenumber of services that a reception system can provide has beensignificantly increased since the reception system has been equippedwith a large-capacity storage device and has been connected to theInternet or data communication channels which enable bidirectionalcommunication.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a method of receivingand processing non-real time services and a broadcast receiver.

Another object of the present invention is to provide a method ofproviding a user interface (UI) for non-real time services and abroadcast receiver.

A further object of the present invention is to provide a method ofenabling shifting between a real-time service guide and a non-real timeservice guide and a broadcast receiver.

Additional advantages, objects, and features of the invention will beset forth in part in the description which follows and in part willbecome apparent to those having ordinary skill in the art uponexamination of the following or may be learned from practice of theinvention. The objectives and other advantages of the invention may berealized and attained by the structure particularly pointed out in thewritten description and claims hereof as well as the appended drawings.

To achieve these objects and other advantages and in accordance with thepurpose of the invention, as embodied and broadly described herein, amethod of processing a non-real time service of a broadcast receiverincludes receiving a signaling information table including additionalinformation on contents configuring a non-real time service and acontent identifier for each content, acquiring and storing theadditional information on contents and the content identifier for eachcontent from the signaling information table, when a non-real timespecific service guide is requested from a real-time specific serviceguide screen, configuring the non-real time specific service guide basedupon the stored additional information and content identifier of thestored contents, thereby displaying a non-real time specific serviceguide screen, and performing a playback or download scheduling functionon the content selected from the non-real time specific service guidescreen.

In the step of displaying the non-real time specific service guidescreen, when a high-light is moved further towards a left side than acurrent time displayed on the real-time (RT) specific service guidescreen, the RT-specific service guide screen may be shifted to thenon-real time (NRT) specific service guide screen. Herein, theRT-specific service guide screen may include a menu button for viewing aprevious program, and the NRT-specific service guide screen may includea menu button for viewing a current program. And, in the step ofdisplaying the non-real time specific service guide screen, when themenu button for viewing a previous program is selected from theRT-specific service guide screen, the RT-specific service guide screenmay be shifted to the NRT-specific service guide screen.

In the step of displaying the non-real time specific service guidescreen, content titles may be sorted based upon an actual broadcastingtime of each content, thereby being displayed on the NRT-specificservice guide screen. The content titles may also be sorted based upon acurrent time, thereby being displayed on the NRT-specific service guidescreen. Alternatively, the content titles may be sorted by category,thereby being displayed on the NRT-specific service guide screen.

In another aspect of the present invention, a broadcast receiverincludes a tuner and a service manager. The tuner receives a signalinginformation table including additional information on contentsconfiguring a non-real time service and a content identifier for eachcontent. And, the service manager acquires and stores the additionalinformation on contents and the content identifier for each content fromthe signaling information table. Herein, the service manager mayconfigure a non-real time specific service guide based upon the storedadditional information and content identifier of the stored contents,when a non-real time specific service guide is requested from areal-time specific service guide screen, thereby displaying a non-realtime specific service guide screen, and may perform a playback ordownload scheduling function on the content selected from the non-realtime specific service guide screen.

When a high-light is moved further towards a left side than a currenttime displayed on the real-time (RT) specific service guide screen, theservice manager may shift the RT-specific service guide screen to thenon-real time (NRT) specific service guide screen. Herein, theRT-specific service guide screen may include a menu button for viewing aprevious program, and the NRT-specific service guide screen may includea menu button for viewing a current program. Also, when the menu buttonfor viewing a previous program is selected from the RT-specific serviceguide screen, the service manager may shift the RT-specific serviceguide screen to the NRT-specific service guide screen.

Herein, the service manager may sort content titles based upon an actualbroadcasting time of each content, thereby displaying the sorted contenttitles on the NRT-specific service guide screen. Also, the servicemanager may sort content titles based upon a current time, therebydisplaying the sorted content titles on the NRT-specific service guidescreen. Alternatively, the service manager may sort content titles bycategory, thereby displaying the sorted content titles on theNRT-specific service guide screen.

It is to be understood that both the foregoing general description andthe following detailed description of the present invention areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiment(s) of the invention andtogether with the description serve to explain the principle of theinvention. In the drawings:

FIG. 1 illustrates a conceptual diagram of providing a real-time (RT)service and a non-real time (NRT) service;

FIG. 2 is a diagram illustrating the relationship between an NRTservice, content item, and files;

FIG. 3 illustrates an embodiment of a protocol stack for a fixed NRTservice according to the present invention;

FIG. 4 illustrates an embodiment of a bitstream syntax structure of avirtual channel table according to the present invention;

FIG. 5 illustrates an embodiment of service type field values in thevirtual channel table of FIG. 4 and respective meanings of the values;

FIG. 6 illustrates another embodiment of values allocated to a servicetype field in the virtual channel table of FIG. 4 and respectivemeanings of the values;

FIG. 7 illustrates an embodiment of a bitstream syntax structure of adata service table (DST) of the present invention;

FIG. 8 illustrates an embodiment of a procedure for obtaining accessinformation of an IP stream that carries an NRT service signalingchannel using a PSI/PSIP table according to the present invention;

FIG. 9 is a flowchart illustrating a procedure for obtaining accessinformation of an IP stream that carries an NRT service signalingchannel using a PSI/PSIP table according to an embodiment of the presentinvention;

FIG. 10 and FIG. 11 illustrate a bitstream syntax structure of aNon-Real Time Service Table (NST) according to the present invention;

FIG. 12 illustrates a bitstream syntax structure of acomponent_descriptor( ) according to an embodiment of the presentinvention;

FIG. 13 illustrates a bitstream syntax of FLUTE file delivery data usingthe component_descriptor( );

FIG. 14 and FIG. 15 illustrate a bitstream syntax structure of aNon-Real Time Information Table (NRT-IT) according to an embodiment ofthe present invention;

FIG. 16 and FIG. 17 respectively illustrate exemplary FDT XML structuresaccording to the present invention;

FIG. 18 illustrates an RT-specific service guide screen according to anembodiment of the present invention;

FIG. 19 to FIG. 21 illustrate examples of a NRT service guide screen,which can be shifted from the RT-specific service guide screen of FIG.18;

FIG. 22 and FIG. 23 illustrate examples of displaying codec informationof a program in message formats according to the present invention;

FIG. 24 illustrates an RT-specific service guide screen according toanother embodiment of the present invention;

FIG. 25 to FIG. 27 illustrate examples of a NRT service guide screen,which can be shifted from the RT-specific service guide screen of FIG.24;

(a) and (b) of FIG. 28 respectively illustrate an RT-specific serviceguide screen according to yet another embodiment of the presentinvention and an exemplary detailed information screen;

(a) and (b) of FIG. 29 respectively illustrate an RT-specific serviceguide screen according to yet another embodiment of the presentinvention and an exemplary detailed information screen; and

FIG. 30 illustrates a block view showing a structure of a broadcastreceiver for fixed NRT services according to an embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

Preferred embodiments of the invention, which can achieve the aboveobjects, will now be described with reference to the accompanyingdrawings. The configuration and operation of the invention, illustratedin the drawings and described below with reference to the drawings, willbe described using at least one embodiment without limiting the spiritand the essential configuration and operation of the invention.

Although most terms of elements in the present invention have beenselected from general ones widely used in the art taking intoconsideration their functions in the invention, the terms may be changeddepending on the intention or convention of those skilled in the art orthe introduction of new technology. Some terms have been arbitrarilyselected by the applicant and their meanings are explained in detail inthe following description as needed. Thus, the definitions of the termsused in the invention should be determined based on the whole content ofthis specification together with the intended meanings of the termsrather than their simple names or meanings.

The term real time (RT) service used in the present invention actuallymeans the real-time service. In other words, it is restricted in time.On the other hand, non-real time (NRT) service refers to non-real time,not RT, service. Thus, NRT service is not restricted in time. Furtherthe data used in NRT service is referred to as NRT service data.

A broadcast receiver according to the present invention receives NRTservice through terrestrial, cable, internet, and the like.

The NRT service is stored in a storage medium of the broadcast receiverand then it is displayed through a display according to a time specifiedby the user or at the user's request. The NRT service is received andstored in a file format according to an embodiment. In an embodiment,the storage medium is an internal HDD attached to the inner part of thebroadcast receiver. In another embodiment, the storage medium may beUniversal Serial Bus (USB) memory or an external HDD connectedexternally with the broadcast receiver.

In order to receive and store the files configuring the NRT service andprovide service to the user, signaling information is needed. Thesignaling information is referred to NRT service signaling informationor NRT service signaling data according to the present invention.

According to the method of receiving IP datagram, NRT service can bedivided into Fixed NRT service and Mobile NRT service. Morespecifically, the Fixed NRT service is provided through fixed broadcastreceiver, and Mobile NRT service is provided through mobile broadcastreceiver.

According to an embodiment of the present invention, Fixed NRT serviceis explained in detail. However, the present invention can also beobviously applied to Mobile NRT service as well.

FIG. 1 illustrates a conceptual diagram of how a RT and an NRT serviceare provided.

The broadcast station, following the conventional method, transmits thecurrent terrestrial broadcast (or mobile broadcast) RT service. At thisjuncture, the broadcast station may provide NRT service using the extrabandwidth or a specific bandwidth left after sending the RT service.Thus, RT service and NRT service are transmitted through a same or adifferent channel. Therefore, a broadcast receiver can be divided intoRT service and NRT service, and in order to provide the user with theNRT service when needed, NRT service signaling information (or NRTservice signaling data) is required. The NRT service signalinginformation (or NRT service signaling data) will be described below indetail.

For example, a broadcast station can transmit broadcast service data inreal time and transmit news clips, weather information, advertisements,push VOD, or the like in non-real time. The NRT service may not onlyprovide such news clips, weather information, advertisements, and pushVOD, but may also provide specific scenes, detailed information onspecific program, preview (trailer) from a real-time broadcast service.

A conventional broadcast receiver (i.e., a legacy device) can receiveand process RT services but cannot receive and process NRT services.Thus, it is a principle that the process of the conventional broadcastreceiver (i.e., a legacy device) is not affected by NRT stream includedin the transmission of RT service. In other words, the conventionalbroadcast receiver does not have a method of handling the NRT serviceeven if it is received.

However, the broadcast receiver (i.e., an NRT device) according to anembodiment of the present invention can combine NRT services and RTservices to provide a variety of services to the user compared to theconvention receiver.

In an embodiment, one NRT service according to the present inventionincludes one or more content item (or content or NRT content) and onecontent item includes one or more files as shown in FIG. 2. The terms“file” and “object” have the same meaning in the description of thepresent invention.

The content item is the minimum unit that can be presentedindependently. For example, when a news program, which includes aneconomic news section, a political news section, and a life newssection, is provided in non-real time, the news program may be an NRTservice and each of the economic news section, the political newssection, and the life news section may be the content item. And each ofthe economic news section, the political news section, and the life newssection may include at least one file.

The NRT service can be transmitted in an MPEG-2 Transport Stream (TS)packet format through a dedicated broadcast channel or the samebroadcast channel as the RT service. In this case, a unique PID istransmitted after being allocated to a TS packet of the NRT service datain order to identify the NRT service. In an embodiment of the presentinvention, IP-based NRT service data is packetized into an MPEG-2 TSpacket for transmission.

The NRT service signaling data required to receive the NRT service datais transmitted through an NRT service signaling channel. The NRT servicesignaling channel is transmitted through a specific IP stream in the IPlayer. Here, the IP stream is also packetized into an MPEG-2 TS packetfor transmission. The NRT service signaling data transmitted through anNRT service signaling channel includes NRT Service Map Table (NST) andNRT Information Table (NRT-IT). In an embodiment of the presentinvention, the NST provides the access information of at least one NRTservice and at least one content item/file that forms NRT services thatoperate in the IP layer. In one embodiment of the present invention,NRT-IT provides detailed information of the content item/file that formsNRT service. In the present invention, the NST and the NRT-IT may bereferred to as Signaling Information Table.

FIG. 3 illustrates a diagram for a protocol stack of an NRT serviceconfigured according to an embodiment of the present invention.

In an embodiment of the present invention, for fixed NRT service, thefile-type NRT service is packetized according to an IP scheme in the IPlayer and then transmitted through a specific virtual channel in anMPEG-2 TS format.

In an embodiment of the present invention, as an example of the MPEG-2based Program Specific Information/Program and System InformationProtocol (PSI/PSIP) table, the presence of the NRT service or theidentification information of the NRT service may be signaled throughthe virtual channel in the Virtual Channel Table (VCT).

In an embodiment of the present invention, the NRT service signalingchannel that transmits NRT service signaling data which signals theaccess information of the IP based NRT service is transmitted in anMPEG-2 TS format after being packetized according to an IP stream in theIP layer through a specific virtual channel.

More specifically, in the broadcast station, NRT content/files arepacketized according to a file transfer protocol scheme and are againpacketized according to an Asynchronous Layered Coding/Layered CodingTransport (ALC/LCT) scheme as shown in FIG. 3. The packetized ALC/LCTdata is again packetized according to an UDP scheme and the packetizedALC/LCT/UDP data is again packetized into ALC/LCT/UDP/IP data accordingto an IP scheme. In the present invention, the packetized ALC/LCT/UDP/IPdata is referred to as an “IP datagram” for ease of explanation.

In addition, NRT service signaling data required to receive the NRTcontent/files is transmitted through an NRT service signaling channel.Here, the NRT service signaling channel is packetized according to aUser Datagram Protocol (UDP) scheme and the packetized UDP data is againpacketized into UDP/IP data according to an IP scheme. In the presentinvention, the UDP/IP data is also referred to as an “IP datagram” forease of explanation. In an embodiment, multicast of the NRT servicesignaling channel is achieved after being encapsulated in an IP datagramhaving a well-known IP destination address and a well-known destinationUDP port number.

In an embodiment of the present invention, IP datagrams of the NRTservice signaling channel and the NRT service are encapsulated in anaddressable section structure and again packetized in an MPEG-2 TSformat. So, one addressable section structure has a format in which asection header and a CRC checksum are added to one IP datagram. Thisaddressable section structure format complies with a Digital StorageMedia Command and Control (DSM-CC) section format for private datatransmission. Thus, the addressable section is also referred to as a“DSM-CC addressable section.” A 188-byte MPEG-2 TS packet can be createdby dividing the addressable section data into 184-byte units and addinga 4-byte MPEG header to each 184-byte unit. At this time, a valueallocated to a PID of the MPEG header is a unique value that canidentify TS packets that carry the NRT service signaling channel and theNRT service.

Program Specific Information (PSI) and Program and System InformationProtocol (PSIP) table section data is also packetized into MPEG-2 TSpackets.

An embodiment of the PSI table may include a Program Map Table (PMT), aProgram Association Table (PAT), or the like and an embodiment of thePSIP table may include a Virtual Channel Table (VCT), a System TimeTable (STT), a Rating Region Table (RRT), an Extended Text Table (ETT),a Direct Channel Change Table (DCCT), a Direct Channel Change SelectionCode Table (DCCSCT), an Event Information Table (EIT), and a MasterGuide Table (MGT).

The MPEG-2 TS packets are modulated according to a predeterminedtransmission scheme, for example, a VSB transmission scheme, in aphysical layer and are then transmitted to the reception system.

In an embodiment of the present invention, the transmission of an NRTservice is determined by signaling through a PSI/PSIP table. Forexample, whether or not an NRT service is transmitted is signaled in aVirtual Channel Table (VCT).

FIG. 4 illustrates a syntax structure of the Virtual Channel Table (VCT)section according to an embodiment.

The VCT section, taking information about the virtual channel forexample, transmits information of channel information for channelselection and PID information for receiving audio and/or video. Thus,when the VCT section is parsed, the PID of the audio and video of thebroadcast program transmitted within the channel along with the channelnumber and channel name is known.

The VCT section syntax includes at least one of table_id field,section_syntax_indicator field, private_indicator field, section_lengthfield, transport_stream_id field, version_number field,current_next_indicator field, section_number field, last_section_numberfield, protocol_version field, num_channels_in_section field.

The VCT section syntax further includes first ‘for’ loop (virtualchannel loop) which repeats for the number indicated in thenum_channels_in_section field value, the first loop includes at leastone of short_name field, major_channel_number field,minor_channel_number field, modulation_mode field, carrier_frequencyfield, channel_TSID field, program_number field, ETM_location field,access_controlled field, hidden field, service_type field, source_idfield, descriptor_length field, or second ‘for’ loop which repeats forthe number of the descriptors included in the first loop. For theconvenience of explanation in the present invention, the second loop isreferred to as the first descriptor loop. The descriptor( ) included inthe first descriptor loop is a descriptor applied in each virtualchannel.

The VCT section syntax may further include a third ‘for’ loop whichrepeats for the number of value indicated byadditional_descriptor_length field and the number of descriptor added inthe VCT section. For the convenience of explanation in the presentinvention, the third loop is referred to as the second descriptor loop.The additional_descriptors( ) included in the second descriptor loop isapplied to all the descriptors described in the virtual channel of theVCT section.

A table_id field illustrated in FIG. 4 indicates a unique identifier oridentification (ID) which identifies that the information transmittedthrough the table is VCT. More specifically, the table_id fieldindicates a value informing that the table corresponding to this sectionis a VCT. For example, a 0xC8 value may be given to the table_id field.

A version_number field indicates the version number of the VCT, thesection_number field indicates the number of this section, and thelast_section_number field indicates the number of the last section of acomplete VCT. The num_channels_in_section field designates the number ofthe overall virtual channel existing within the VCT section.

A short_name field in the first ‘for’ loop indicates the name of avirtual channel. The major_channel_number field indicates a ‘major’channel number associated with the virtual channel defined within thefirst loop and the minor_channel_number field indicates ‘minor’ channelnumber. Thus, each channel number should be connected to the major andminor channel numbers, and the major and minor channel numbers are usedas user reference numbers for the corresponding virtual channel.

A program_number field is shown for connecting the virtual channelhaving an MPEG-2 program association table (PAT) and program map table(PMT), and matches the program number within the PAT/PMT. Here, the PATdescribes the elements of a program corresponding to each programnumber, and the PAT indicates the PID of a transport packet transmittingthe PMT. The PMT describes the affiliated information and the PID listof the transport packet in which the identification number and theaudio/video information of a program is transmitted in bit sequence.

A service_type field indicates the service type within the correspondingvirtual channel.

In an embodiment, the virtual channel may include at least one RTservice and at least one NRT service including audio and/or video.

In this case, service type values may be allocated as shown in FIG. 5and a value of 0x04 representing an ATSC-data-only service may be usedto indicate that an NRT service is provided through the virtual channel.

In another embodiment, the virtual channel may only include one or moreNRT service. In such a case, as shown in FIG. 6, a new service_typefield value of 0x08 may be defined to indicate that an NRT service isprovided through the virtual channel.

A source_id field indicates a program source connected to thecorresponding virtual channel.

The term “source” refers to a specific source such as a video, text,data or audio source. The source_id field has a unique value in atransport stream in which a VCT is transmitted.

On the other hand, data service table (DST) may be received through PIDincluded in the service_location_descriptor of the VCT, and through theDST, the types of the application and the detailed information of thedata broadcast stream transmitted through the channel is known.

In the present invention, NRT application (NRT service) is identifiedthrough the DST.

FIG. 7 illustrates the DST section syntax structure according to anembodiment.

A sdf_protocol_version field (8-bit) indicates the version of theService Description Framework protocol.

An application_count_in_section field (8-bit) indicates the number ofapplications listed within the DST section.

A compatibility_descriptor( ) field indicates that the correspondingstructure includes DSM-CC compatible descriptor. The object is to signalthe compatibility requests of the application of the platform receivedto determine the ability to use the corresponding data service.

An app_id_byte_length field (16-bit) indicates the number of bytes usedto identify the application.

An app_id_description field (16-bit) indicates the format and thesemantics of the next application identification bytes. As described inthe table 1 below, ‘0x0003’ is newly assigned to identify that thecorresponding application is an NRT application. The assigned value of‘0x0003’ is just an exemplary value and the scope of this application isnot limited to the value.

TABLE 1 Application Identifier Value Format 0x0000 DASE application0x0001 ATSC reserved 0x0002 ATSC A/92 Application 0x0003 NRT Application0x0004-0x7FFF ATSC reserved 0x8000-0xFFFF User private

An app_id_byte field (8-bit) describes the byte of the applicationidentifier.

A tap_count field (8-bit) indicates the number of Tap( ) structure usedby the corresponding application.

A protocol_encapsulation field (8-bit) indicates the type of theprotocol encapsulation used to transmit the specific data element inreference with the Tap( ) field.

An action_type field (7-bit) instructs the character of the data inreference with the Tap( ) field.

A resource_location field (1-bit) indicates the location of theassociation_tag field that matches the association_tag value listedwithin the next Tap structure. If the value of the corresponding fieldis ‘0,’ then the matching association_tag exist in the PMT of thecurrent MPEG-2 program. Oppositely, if the value is ‘1,’ then thematching association_tag exists in the DSM-CC Resource Descriptor in theNetwork Resources Table of the corresponding data service.

A Tap( ) field, for example, is defined in a unique structure includingthe following. The tap_id field (16-bit) is used by the application toidentify the data elements. The range of the value of tap_id isdetermined by the app_id_byte fields related to Tap( ) within the DST.The value of tap_id is selected by the data service provider. Further,it is used in application to handle the data elements.

A Use field (16-bit) is used to specify the communication channelreferenced by the association_tag.

An association_tag field (16-bit) uniquely identifies one from thelisted DSM-CC resource descriptor within the Network Resource Table orlisted data elementary stream within the PMT.

A Selector( ) field indicates a unique data element that can be used inthe communication channel referenced by association_tag field or in thedata elementary stream.

A tap_info_length field (16-bit) indicates the number of bytes of thedescriptors of the next field of the corresponding field.

A tap_info_length field (16-bit) indicates the number of bytes of thedescriptors of the next field of the corresponding field.

An app_info_length field (8-bit) indicates number of bytes of thedescriptor of the next corresponding field.

A descriptor( ) field follows the descriptor format.

An app_data_length field (16-bit) indicates length of the app_data_bytefields in bytes.

An app_data_byte (8-bit) describes the private data fields differentfrom input parameters associated with the application as 1 byte.

A service_info_length field (8-bit) indicates number of byte unit of thenext descriptors.

A descriptor( ) field follows the descriptor format.

A service_private_data_length field (16-bit) indicates length of byteunit of the private fields.

A service_private_data_byte field (8-bit) describes the private fieldsas 1 byte.

FIG. 8 illustrates a method in which an NRT service is received andprovided using an ATSC A/90 standard for carrying (or transmitting) adata broadcast stream and an ATSC A/92 standard for transmitting an IPmulticast stream in a broadcast receiver according to the presentinvention.

Namely, information of a stream that constitutes each virtual channel issignaled in an ES_loop of a PMT or a service location descriptor of aVCT. For example, an NRT service stream can be transmitted through thevirtual channel in the case where the service type of the VCT is 0x02(i.e., digital A/V Data), 0x04 (i.e., data only), or 0x08 (i.e., NRTonly service), as shown in FIG. 5 or FIG. 6. At this time, when thestream_type field included in the service location descriptor (or the ESloop of the PMT) has a value allocated 0x95 (i.e., DST transmission),this indicates that a data broadcast is transmitted. A normal A/V istransmitted if the service location descriptor has no value forstream_type field or does not have a value of 0x95 allocated. Therefore,if the stream_type field included in the service location descriptor hasa value of 0x95, the Elementary_PID field value is a PID of a DataService Table (DST). Thus, the DST can be received through theElementary_PID field.

The type of the application and details of a data broadcast streamtransmitted through this channel can be determined through the DST. Inthe present invention, an NRT application (i.e., an NRT service) isidentified using the DST.

That is, an App_id_description field of the DST specifies the format andanalysis of application identification bytes subsequent to this field.In an embodiment of the present invention, ‘0x0003 ’ is allocated to theApp_id_description field in order to identify the NRT application. Theillustrated value (number) is only an example and does not limit thescope of the present invention.

If the App_id_description field value is ‘0x0003 ’, anApplication_id_byte value subsequent to this field is a service ID ofthe NRT application. A service ID of the NRT application may have a URIvalue that globally and uniquely identifies the corresponding service.

After the NRT application is identified as described above, a PID of anMPEG-2 TS packet separated from the IP datagram of the NRT servicesignaling channel is located through the Tap information. Then, an IPdatagram that carries the NRT service signaling channel can be obtainedfrom MPEG-2 TS packets having the PID found through the tap informationand NRT service signaling data can be obtained from the obtained IPdatagram. Here, well-known IP access information, i.e., a well-known IPaddress and a well-known UDP port number can be used as the IP accessinformation of the NRT service signaling channel.

That is, an asynchronous IP stream is transmitted if aProtocol_encapsulation field value in the DST is 0x04 and a device_idvalue indicating the destination address is transmitted through aselector_bytes value if a Selector_type field value is 0x0102. Amultiprotocol_encaplsulation_descriptor is used in order to accuratelyanalyze the selector_bytes value and signals the number of valid bytesincluded in the device_id value. As a result, IP multicasts address (oraddress range) of the NRT service signaling channel transmitted throughthe PID can be determined through the Tap information.

Accordingly, the IP multicast address (or address range) is accessed andan IP stream, i.e., an IP packet, is received and NRT service signalingdata is extracted from the received IP packet.

NRT service data, i.e., NRT content/files, is received based on theextracted NRT service signaling data and the received data can be storedin a storage medium or can be displayed on a display.

In another embodiment of the present invention, the NRT service can besignaled using a new value, for example, 0x96 instead of 0x95 as thestream type field value of the DST. This embodiment aims to eliminatethe risk that the conventional receiver may malfunction with the NRTservice which is a new application, in the case where the conventionalreceiver operates by determining whether or not a data broadcast streamis present based only on whether or not a stream having a stream typevalue of 0x95 is present. In this case, if a new stream type is defined,it will be possible to allow the conventional receiver to ignore thisstream type, thereby guaranteeing backward compatibility.

FIG. 9 is a flowchart illustrating the process of NRT service signalingdata and the process of extracting the NRT service data.

In an embodiment, as shown in FIG. 9, the service_type field in the VCThas a value of 0x08 as in FIG. 6, indicating that at least one NRTservice is transmitted through the relevant virtual channel.

After a power of a receiver has been turned on, if a default channel ora channel by a user is selected (S1001), the receiver receives a VCT ora PMT (S1002). And then the receiver determines whether NRT serviceexists or not by parsing the VCT (S1003). This can be done throughlooking at the service_type in the received virtual channel loop withinthe VCT. The (S1001) step is processed in the tuner and the(S1002)/(S1003) step is processed in the PSI/PSIP section handler.

For instance, if a value of the service_type is not set to ‘0x08 ’, therelevant virtual channel will not transmit NRT service. The virtualchannel will then transmit conventional service (i.e., legacy ATSCservice), the receiver processes according to the information includedin the virtual channel.

If the service_type field has a value of 0x08, the virtual channel willtransmit NRT service. In such a case, service location descriptor in thevirtual channel of the VCT is parsed to extract the PID of DST (S1004).Then, using the extracted PID, DST is received (S1005). The (S1004) and(S1005) step is processed through the demultiplexer controlled by theservice manager.

It is then determined whether the corresponding service provided on theselected channel is an NRT service from the received DST (S1006).

The determination of a presence of the NRT service can be performed bychecking the value of the App_id_description field.

For instance, the value of the App_id_description is set to ‘0x0003,’ inthis present invention to identify that the service is an NRTapplication (i.e., NRT service). The value (number) is only an exampleand will not limit the scope of the present invention.

If the value of the App_id_description field is ‘0x0003,’ the value ofthe subsequent Application_id_byte becomes the value of service ID ofthe NRT application (i.e., NRT service). As a result of identifying theNRT application, a Tap is extracted to locate the PID of the MPEG-2 TSpacket separated from the IP datagram of the NRT service signalingchannel (S1007). And, stream PID including association_tag of the Tap isextracted from the PMT (S1008). The steps of (S1006) to (S1008) areprocessed by the service manager or the PSI/PSIP section handler.

After receiving and decapsulating the MPEG-2 TS packets corresponding tothe stream PID, i.e, removing the MPEG-2 header, a DSM-CC addressablesection is recovered (S1009). This process is handled by the addressablesection handler.

Subsequently, after removing section header and CRC checksum from theDSM-CC addressable section, IP datagram transmitting the NRT servicesignaling channel is recovered (S1010), and the NRT service signalingdata is obtained from the recovered IP datagram (S1011). At this time,the access information of the IP datagram transmitting the NRT servicesignaling channel is received from a well-known destination IP addressand well-known destination UDP port number.

If a value of Protocol_encapsulation in the DST is set to ‘0x04 ’, anasynchronous IP datagram is transferred. If Selector_type is set to‘0x0102’, a value of device_id indicating a destination address isdelivered via selector_bytes. In order to accurately analyze the valueof the selector_bytes, multiprotocol_encapsulation_descriptor is usedand the number of the valid byte within the device_id is signaled. As aresult, the IP Multicast address (or address range) of the NRT servicesignaling channel transmitted through PID of the Tap information isknown.

Thus, by accessing the IP Multicast address (or address range), IPstream, i.e., IP packet is received, and the NRT service signaling datais extracted from the IP packet.

Based on the extracted NRT service signaling data, NRT service data,i.e., NRT content item/files can be received and stored in a storageunit or can be displayed through a display.

In an embodiment, the NRT service signaling data transmitted through theNRT service signaling channel may include NRT Service Map Table (orService Table: NST) and NRT Information Table (NRT-IT).

In an embodiment, IP datagrams of the NST and NRT-IT has the samewell-known IP address and well-known UDP port number. Therefore, thedetermination of NST and NRT-IT included in the NRT service signalingdata is done through table identifier. Thus, the table identifier can bethe table_id of the corresponding table or the header of the tablesection, and when necessary, table_id_extension can be referred to inorder to identify the table.

NRT Service Map Table (NST)

The NST provides access information of the NRT service. In anembodiment, the NST has a similar table to the MPEG-2 Private sectionformat.

The NST provides access information of IP based NRT services included inthe virtual channel. For example, the NST provides access information ofeach FLUTE sessions that configures one NRT service.

Here, whether one NST is configured with one session or plurality ofsessions is determined through the table_id field, section_number field,last_section_number field, and the like. And the table may be completedby removing the IP header and the UDP header of the IP datagrams of theNRT service signaling channel and gathering sections having the sametable identifier. For example, by gathering the sections having tableidentifier allocated for NST, the NST is completed.

FIG. 10 and FIG. 11 illustrate a bitstream syntax structure of an NSTsection according to an embodiment of the present invention. The detailof each field of the NST section is explained in the following.

Although the syntax is written in an MPEG-2 private section format forbetter understanding, the data may be in any format. For example, it ispossible to use another method in which the syntax is expressed in aSession Description Protocol (SDP) format and is then signaled through aSession Announcement Protocol (SAP).

In FIG. 10 and FIG. 11, a table_id field includes an 8-bit unsignedinteger number that indicates the type of table section being defined inNRT Service Table (NST).

A section_syntax_indicator is a 1-bit field that shall be set to ‘0’ toalways indicate that this table is derived from the “short” form of theMPEG-2 private section table.

A private_indicator (1-bit) indicates whether the type of thecorresponding section follows the private section type or not. (Thisfield that shall be set to ‘1’)

A section_length is a 12-bit field. It specifies the number of remainingbytes this table section immediately following this field. The value inthis field shall not exceed 4093 (0xFFD)).

A table_id_extension field is a 16-bit field and is table-dependent. Itshall be considered to be logically part of the table_id field providingthe scope for the remaining fields. The table_id_extension fieldincludes NST_protocol_version fields.

The NST_protocol_version field is an 8-bit unsigned integer field whosefunction is to allow, in the future, this NST to carry parameters thatmay be structured differently than those defined in the currentprotocol. At present, the value for the NST_protocol_version field shallbe zero. Non-zero values of NST_protocol_version may be used by a futureversion of this standard to indicate structurally different tables.

A version_number field (5-bit) indicates the version number of the NST.

A current_next_indicator field is a one-bit indicator, which when se to‘1’ shall indicate that the NST sent is currently applicable. When thebit is set to ‘0’, it shall indicate that the table sent is not yetapplicable and will be the next table to become valid. This standardimposes no requirement that “next” tables (those withcurrent_next_indicator set to ‘0’) must be sent. An update to thecurrently applicable table shall be signaled by incrementing theversion_number field).

A section_number field is an 8-bit field that shall give the sectionnumber of this NST section. The section_number field of the firstsection in an NST shall be ‘0x00’. The section_number field shall beincremented by 1 with each additional section in the NST.

A last_section_number field is an 8-bit field that shall give the numberof the last section (i.e., the section with the highest section_number)of the NST of which this section is a part).

A num_NRT_services field is an 8-bit field that specifies the number ofservices in this NST section.

A ‘for’ loop, which is also referred to as an “NRT service loop”, isexecuted for the number of times as the number of NRT servicescorresponding to the num_NRT_services field value in providing signalinginformation of a plurality of NRT services. Thus, signaling informationof the corresponding NRT service is indicated for each of the NRTservices included in the NST section. Here, the following fieldinformation may be provided for each NRT service.

An NRT_service_id field is a 16-bit unsigned integer number that shalluniquely identify this NRT service within the scope of this NRT section.The NRT_service_id field of a service shall not change throughout thelife of the service. To avoid confusion, it is recommended that if aservice is terminated, then the NRT_service_id field for the serviceshould not be used for another service until after a suitable intervalof time has elapsed.

An NRT_service_status field is a 2-bit enumerated field that shallidentify the status of this NRT Service. The most significant bit shallindicate whether this NRT Service is active (when set to ‘1’) orinactive (when set to ‘0’) and the least significant bit shall indicatewhether this NRT Service is hidden (when set to ‘1’) or not (when set to‘0’). Hidden services are normally used for proprietary applications,and ordinary receiving devices should ignore them.

A SP_indicator field is a 1-bit field that indicates when set to 1,service protection is applied to at least one of the components neededto provide a meaningful presentation of this NRT Service.

A Short_NRT_service_name_length field (3-bit) instructs the number ofbyte pairs within the Short_NRT_service_name field.

A Short_NRT_service_name filed (16*m bit) indicates a short name of theNRT service. This field may be filled with null data (for example, 0x00)when the NRT service has no short name.

An NRT_service_category field is a 6-bit enumerated type field thatshall identify the type of service carried in the NRT.

A num_components field is a 5-bit field that specifies that number of IPstream components in this NRT Service.

An IP_version_flag is a 1-bit indicator, which when set to ‘0’ shallindicate that source_IP_address, NRT_service_destination_IP_address, andcomponent_destination_IP_address fields are IPv4 addresses. The value of‘1’ for this field is reserved for possible future indication thatsource_IP_address, NRT_service_destination_IP_address, andcomponent_destination_IP_address fields are for IPv6.

A source_IP_address_flag field is a 1-bit Boolean flag that shallindicate, when set, that a source IP address value for this NRT Serviceis present to indicate a source specific multicast.

An NRT_service_destination_IP_address_flag field is a 1-bit Boolean flagthat indicates, when set to ‘1’, that anNRT_service_destination_IP_address field value is present, to serve asthe default IP address for the components of this NRT Service.

A source_IP_address field is a 32 or a 128 bit field that shall bepresent if the source_IP_address_flag field is set to ‘1’ and shall notbe present if the source_IP_address_flag field is set to ‘0’. Ifpresent, this field shall contain the source IP address of all the IPdatagrams carrying the components of this NRT Service. The conditionaluse of the 128 bit-long address version of this field is to facilitatepossible use of IPv6 in the future, although use of IPv6 is notcurrently defined.

An NRT_service_destination_IP_address field is a 32 or a 128 bit fieldthat shall be present if the NRT_service_destination_IP_address_flagfield is set to ‘1’ and shall not be present if theNRT_service_destination_IP_address field is not present, then thecomponent_destination_IP_address field shall be present for eachcomponent in the num_components loop. The conditional use of the 128bit-long address version of this field is to facilitate possible use ofIPv6 in the future, although use of IPv6 is not currently defined.

A ‘for’ loop, which will also be referred to as a “component loop,” isexecuted as much as the number of times as the number of componentscorresponding to the num_components field value to provide accessinformation of a plurality of components. This provides accessinformation of each component included in the NRT service. Here, thefollowing field information may be provided for each component. In anembodiment, one component corresponds to one FLUTE session.

An essential_component_indicator field is a 1-bit indicator which, whenset to ‘1’, shall indicate that this component is an essential componentfor the NRT Service. Otherwise, this field indicates that this componentis an optional component.

A port_num_count is a 6-bit field that shall indicate the number ofdestination UDP ports associated with this UDP/IP stream component. Thevalues of the destination UDP port numbers shall start from thecomponent_destination_UDP_port_num field and shall be incremented byone.

A component_destination_IP_address_flag field is a 1-bit Boolean flagthat shall indicate, when set to ‘1’, that thecomponent_destination_IP_address field is present for this component.

A component_destination_IP_address field (32 or 128 bit) shall bepresent if the component_destination_IP_address_flag field is set to ‘1’and shall not be present if the component_destination_IP_address_flagfield is set to ‘0’. When this field is present, the destination addressof the IP datagrams carrying this component of the NRT Service shallmatch the address in this field. When this field is not present, thedestination address of the IP datagrams carrying this component shallmatch the address in the NRT_service_destination_IP_address field. Theconditional use of the 128 bit-long address version of this field is tofacilitate possible use of IPv6 in the future, although use of IPv6 isnot currently defined.

A component_destination_UDP_port_num field is a 16-bit unsigned integerfield that represents the destination UDP port number for this UDP/IPstream component.

A num_component_level_descriptors field (4-bit) indicates the number ofdescriptors providing the additional information of the component level.

The same number of the component_level_descriptor( ) is included in thecomponent loop providing additional information as the number of thefield value of the num_component_level_descriptors.

A num_NRT_service_level_descriptors field (4-bit) indicates the numberof descriptors that provide additional information about the NRT servicelevel.

The same number of the NRT_service_level_descriptor( ) are included inNRT service loop as the number of the field value ofnum_NRT_service_level_descriptors to provide additional informationabout the NRT service.

A num_virtual_channel_level_descriptors field (4-bit) indicates thenumber of descriptors which provides additional information about thevirtual channel level.

The same number of virtual_channel_level_descriptor( ) included in thevirtual channel loop as the number of the field value of thenum_virtual_channel_level_descriptors to provide additional informationof the virtual channel.

FIG. 12 illustrates an embodiment of a bitstream syntax structure of acomponent_level_descriptors( ). The component_descriptor( ) is used asone of the component level descriptor component_level_descriptors( ) ofthe NST and describes additional signaling information of thecorresponding component.

The following is a description of each field of thecomponent_descriptor( ).

In FIG. 12, a descriptor_tag field (8-bit) is a descriptor identifierand it can be set as an identifier that identifies thecomponent_descriptor( ).

A descriptor_length field (8-bit) describes the remaining length of thedescriptor starting after the descriptor_length field and to the end ofthis descriptor, in bytes.

A component_type field (7-bit) shall identify the encoding format of thecomponent. The value may be any of the values assigned by IANA for thepayload_type of an RTP/AVP stream, or it may be any of the valuesassigned by ATSC, or it may be a “dynamic value” in the range 96-127.For components consisting of media carried via RTP, the value of thisfield shall match the value in the payload_type field in the RTP headerof the IP stream carrying this component. Note that additional values ofthe component_type field in the range of 43-71 can be defined in futureversions of this standard.

A component_encryption_flag (1-bit) informs whether the correspondingcomponent is encrypted or not.

A Num_STKM_streams field (8-bit) indicates the number STKM streams ifcomponent_encryption_flag has been encrypted. (The num_STKM_streamsfield (8-bit) is an 8-bit unsigned integer field that shall identify thenumber of STKM streams associated with this component.

A STKM_stream_id field (8-bit) is repeated as much as the field value ofNum_STKM_streams and indicates a value that identifies a STKM streamthat can acquire a key required for decryption.

An NRT_component_data (component_type) element provides the encodingparameters and/or other parameters necessary for rendering thiscomponent. The structure of the component_data is determined by thevalue of component_type field.

For example, if the component_type field value is 35 thenNRT_component_data (component_type) field provides component data forH.264/AVC video stream.

In another example, if the component_type field value is 38 thenNRT_component_data (component_type) field provides data for FLUTE filedelivery as shown in FIG. 13.

One NRT service can be included in multiple FLUTE sessions. Thus, oneNRT service may be configured with plurality of FLUTE sessions. EachFLUTE session may be signaled using NRT_component_data( ) as shown inFIG. 13.

FIG. 13 illustrates an example of the bitstream syntax structure ofNRT_component_data( ) that provides data for FLUTE file deliveryaccording to the present invention. The following explains each field inthe NRT_component_data( ).

A TSI field (16-bit unsigned integer) shall be the Transport SessionIdentifier (TSI) of FLUTE session.

A session_start_time field (16-bit) indicates the start time of theFLUTE session. If the field values are all ‘0’, then it can beinterpreted that the FLUTE session has already begun.

A session_end_time field (16-bit) indicates the end time of the FLUTEsession. If the field values are all ‘0,’ then it can be interpretedthat the FLUTE session continues for unlimited amount of time.

A tias_bandwidth_indicator field (1-bit) flags the inclusion of TIASbandwidth information. This bit shall be set to ‘1’ to indicate the TIASbandwidth field is present, and it shall be set to ‘0’ to indicate theTIAS bandwidth field is absent.

An as_bandwidth_indicator field (1-bit) flags the inclusion of ASbandwidth information. This bit shall be set to ‘1’ to indicate the ASbandwidth field is present, and it shall be set to ‘0’ to indicate theAS bandwidth field is absent.

A FEC_OTI_indicator field (1-bit) indicates whether FEC ObjectTransmission Information is provided.

A tias_bandwidth field (16-bit) exists when the as_bandwidth_indicatorfield value is set to ‘1’ and it indicates the maximum bandwidth. Also,it shall be one one-thousandth of the Transport Independent ApplicationSpecific maximum bandwidth as defined in RFC 3890, rounded up to thenext highest integer if necessary. This gives the TIAS bandwidth inkilobits per second.

An as_bandwidth field (16-bit) exists when the as_bandwidth_indicatorfield value is set to ‘1’ and it indicates the maximum AS bandwidth.Also, this value shall be the Application Specific maximum bandwidth asdefined in RFC 4566. This gives the AS bandwidth in kilobits per second.

A FEC_encoding_id field exits when the FEC_OTI_indicator field value isset to ‘1’ and indicates FEC ID used in corresponding FLUTE session.(FEC encoding ID used in this FLUTE session, as defined in RFC 3926).

A FEC_instance_id field exists when the FEC_OTI_indicator field value isset to ‘1’ and indicates FEC instance ID used in the corresponding FLUTEsession. (FEC instance ID used in this FLUTE session, as defined in RFC3926).

The information necessary to receive FLUTE session is provided bysignaling the parameters through the NRT_component_data( ) of thecomponent_descritpor( ) within the component loop.

In other words, according to the time information set by thesession_start_time field and the session_end_time field, thecorresponding FLUTE session is opened and files and the FDT (FileDescription Table) that describes the signaling information of the filesthat configures NRT service (or content) is received. The FDT is used totransmit the list of all the content items, and also providesinformation necessary in acquiring content item and the files includedin the content item.

For example, each file configuring a content item may be identified byusing a Content-Location indicated in an FDT of a FLUTE session. TheContent-Location indicates an identifier that can identify thecorresponding file. Herein, the Content-Location is configured in ananyURI (Uniform Resource Identifier) format. More specifically, theContent-Location value is a locator including the file name.

At this point, a content linkage identifying the corresponding contentitem may be allocated (or assigned) for each file level or instancelevel of the FDT. In this case, each file may be identified by usingcontent linkage, transfer object identifier (TOI), and Content-Locationvalues indicated in the FDT of the FLUTE session. Herein, the contentlinkage corresponds to an identifier that can identify the content item,and the TOI corresponds to an identifier that can identify a transportobject, i.e., file being transmitted through the FLUTE session. Forexample, when the TOI value is equal to ‘0’, the file corresponds to theFDT. More specifically, the TOI value of each file configuring thecontent item is greater than ‘0’.

NRT Information Table (NRT-IT)

FIGS. 14 and 15 are bitstream syntax of an NRT-IT section according toan embodiment of the present invention.

The bit-stream syntax of the NRT-IT section is described in MPEG-2Private section format for ease of understanding the bit-stream syntaxof the NRT-IT section, but the format of the data can be in otherformats as well. For example, signaling through Session AnnouncementProtocol (SAP) described by Session Description Protocol (SDP) type isalso possible.

An NRT-IT of NRT service signaling data according to an embodiment ofthe present invention includes information describing a downloadablecontent item to store a content item in a broadcast receiver.

Here, the determination whether one NRT-IT is configured through onesection or plurality of sections can be known through the table_idfield, section_number field, last_section_number field, and the like,within the NRT-IT section. And the table may be completed by removingthe IP header and the UDP header of the IP datagrams of the NRT servicesignaling channel and gathering sections having the same tableidentifier. For example, by gathering the sections having tableidentifier allocated for NRT-IT, the NRT-IT is completed.

The detailed description of the NRT-IT section fields illustrated inFIGS. 14 and 15 are described below.

A table_id field (8-bit) is set to 0xTBD to identify this table sectionas belonging to the Non-Real-Time Information Table.

A service_id field (16-bit) specifies the service_id field associatedwith the NRT service offering content items described in this section.

An NRT_IT_version_number field (5-bit) indicates the version number ofthis NRT-IT instance, where NRT-IT instance is defined as the set of oneor more NRT_information_table_section( ) having common values forservice_id field, current_next_indicator field, protocol_version field,and time_span_start field. The version number is incremented by 1 modulo32 when any field in the NRT-IT instance changes.

A current_next_indicator field (1-bit) is always set to ‘1’ for NRT-ITsections; the NRT-IT sent is always currently applicable.

A protocol_version field (8-bit) is set to zero. The function ofprotocol_version field is to allow, in the future, this table type tocarry parameters that may be structured differently than those definedin the current protocol. At present, the only valid value forprotocol_version field is zero. Non-zero values of protocol_versionfield may be used by a future version of this standard to indicatestructurally different tables.

A time_span_start field (32-bit) represents the start of the time spancovered by this instance of the NRT-IT, expressed as the number of GPSseconds since 00:00:00 UTC, Jan. 6, 1980. The time of day oftime_span_start field is aligned to minute 00 of the hour. The valuezero for time_span_start field indicates the time period covered by hisNRT-IT instance began in the indefinite past. The value oftime_span_start field is the same for each section of a multi-sectionedNRT-IT instance. The values of time_span_start field andtime_span_length field are set such that the specified time span doesnot overlap with any other NRT-IT instance in this IP subnet.

A time_span_length field (11-bit) indicates the number of minutes,starting at the time indicated by time_span_start field, covered by thisinstance of the NRT-IT. Once established, the value of time_span_lengthfield for a given value of time_span_start field does not change. Avalue of time_span_length field of zero means this NRT-IT instancecovers all time starting at time_span_start field into the indefinitefuture. If the value of time_span_start is zero, time_span_length fieldhas no meaning. The value of time_span_length field is the same for eachsection of a multi-sectioned NRT-IT instance. The values oftime_span_start field and time_span length field are set such that thespecified time span does not overlap with any other NRT-IT instance inthis IP subnet.

A num_items_in_section field (8-bit) indicates the number of contentitems described in this NRT-IT section.

The ‘for’ loop (also referred to as content item loop) is executed fornumber of content items corresponding to the value of thenum_items_in_section field and provides signaling information aboutplurality of content items. Thus, the signaling information of thecontent item of each content item included in the NRT servicecorresponding to the service_id field value is indicated. The followingdescribes the field in each content item that may provide theinformation.

The content_linkage field is a 32-bit field having a value ranging from0x0001 to 0xFFFF. The content_linkage field indicates an identificationnumber of the corresponding content (or content item). Herein, the value0x0000 is not used. The content_linkage field performs two linkagefunctions. One linkage function is to link the metadata included in anNRT-IT with at least one or more files included in an FLUTE FDT, whichis associated with the NRT service. The other linkage function is toform a TF_id field, i.e., an identifier for a Text Fragment in a TextFragment Table. The value of the content_linkage field corresponds toone of the values of the FDT-Content-Linkage elements or to one of thevalues of the File-Content-Linkage elements within the FLUTE FDT foreach of the files associated with the content item. The precedence rulesmay be applied when matching each content_linkage value with thecorresponding content linkage elements in the FLUTE FDT.

An updates_available field (1-bit) indicates whether the correspondingcontent item is updated. For example, when the content item is includedin an NRT service that is ended after once service, the field is set to‘0’. When the content item is one more updated, the field is set to ‘1’.That is, the updates_available field specifies, when set to ‘1,’ thatthe referenced content item(s) will be updated. When theupdates_available field is set to ‘0,’ updates are not expected to beprovided for the associated content item(s), and broadcast receivers arenot expected to look for them.

A TF_available field is Boolean flag, this field specifies, when set to‘1’ that a Text Fragment is present in a Text Fragment Table in theservice signaling channel. When the field is set to ‘0,’ no TextFragment is included in the service signaling channel for this contentitem.

A low_latency field is Boolean flag, this field specifies, when set to‘1,’ that the content is available within the current digital transportwith a low enough latency that its retrieval should be attempted whilethe user waits. When the field is set to ‘0’, retrieval latency islonger and the user interface should suggest to the user to return laterfor viewing.

A playback_length_in_seconds field (20-bit) specifies the duration ofplayback of the content, in seconds. For content consisting only of textand/or still images, the value zero is used. For content that includesaudio or audio/video content, the playback_length_in_seconds fieldindicates the playback length of the audio or audio/video content.

A content_length_included field is Boolean flag, this field indicates,when set to ‘1,’ that the content_length field is present in thisiteration of the “for” loop. Setting this field to ‘0’ indicates thecontent_length field is not present in this iteration of the “for” loop.

A playback_delay_included field is Boolean flag, this field indicates,when set to ‘1,’ that the playback_delay field is present in thisiteration of the “for” loop. Setting this field to ‘0’ indicates theplayback_delay field is not present in this iteration of the “for” loop.

An expiration_included field is Boolean flag, this field indicates, whenset to ‘1,’ that the expiration field is present in this iteration ofthe “for” loop. Setting this field to ‘0’ indicates the expiration fieldis not present in this iteration of the “for” loop.

A duration field (12-bit) in the range 1 to 2880 specifies the expectedcycle time, in minutes, of the carousel containing the referencedcontent item. A broadcast receiver is expected to use the durationparameter to determine the amount of time needed to capture thereferenced content.

A content_length field (40-bit), when present, represents the total sizein bytes of the content item or items. This item is used by thebroadcast receiver to determine if enough memory is available to storeit before downloading is attempted.

A playback_delay field (20-bit) counts of the number of secondsfollowing reception of the first byte of the associated content thebroadcast receiver waits before playback may start, while buffering theincoming stream. A value of zero indicates playback may commenceimmediately. When playback_delay field is not provided, the broadcastreceiver is expected to retrieve the complete file or file set prior toplayback.

An expiration field is a 32-bit field, which indicates an expirationtime of the corresponding content.

A content_name_length field is an 8-bit field, which indicates the totallength of the subsequent content_name_text( ) field in byte units. Thecontent_name_text( ) field specifies a title of a corresponding content(or content item) in a multiple string structure (MSS).

A content_descriptors_length field is a 12-bit field, which indicatesthe total length of the subsequent content_descriptor( ) field in byteunits.

The content_descriptor( ) field corresponds to a descriptor providingadditional information on a content level, the content_descriptor( )field being individually applied to each content (or content item).

A descriptors_length field is a 10-bit field, which indicates the totallength of the subsequent descriptor( ) field in byte units.

The descriptor( ) field is commonly applied to all contents (or contentitems) being described in the current NRT-IT section.

Also, according to an embodiment of the present invention, information(or parameter) essentially required for rendering content/files, whichconfigure the NRT service, e.g., encoding information and decodingparameters applied to the video, audio, and so on, included in an NRTservice or content, is transmitted to the broadcast receiver. Forexample, the encoding information may correspond to codec information ofthe video and audio included in the NRT service or content.

The encoding information and decoding parameter may be signaled throughan in-line field of the descriptor, thereby being transmitted, or may besignaled through an in-line field of the NST or NRT-IT, thereby beingtransmitted. At this point, the descriptor is included in any one of aFLUTE session level or NRT service level, or component level or contentlevel.

Also, according to an embodiment of the present invention, the encodinginformation and decoding parameter are provided in text formatsexpressed as a multi-purpose Internet mail extensions (MIME) type. Morespecifically, the broadcast receiver according to the present inventionindicates and transmits the encoding information and decoding parameterin a text format.

Meanwhile, an NRT service according to the present invention includes atleast one or more contents (or content items or NRT contents), as shownin FIG. 2, and one content includes at least one or more files.

And, the files included in the content are provided to the NRT throughthe FLUTE session. However, the files included in the content may beprovided not only through the FLUTE session, but also through theInternet.

At this point, according to an embodiment of the present invention,Internet access information of the content is provided through a contentlevel descriptor of the NRT-IT. In the description of the presentinvention, the corresponding descriptor will be referred to as aninternet location descriptor internet_location_descriptor( ). Theinternet location descriptor includes a URL( ) field, which indicatesthe internet URL of the content.

Also, according to another embodiment of the present invention, anindicator field indicating whether or not the content is also beingprovided through (or available on) the internet is added to the NRT-ITfield. In the description of the present invention, the field is thiscase will be referred to as an available_on_internet field. When thevalue of the available_on_internet field indicates that thecorresponding content is available on the internet, the Content_Locationattribute within the FLUTE FDT corresponding to each file that belongsto the content indicates the internet URL of the file.

More specifically, when the value of the available_on_internet fieldwithin the content loop of the NRT-IT indicates that the correspondingcontent is available on the internet, the Content_Location attribute ofeach file within the FLUTE FDT indicates the internet address of thecorresponding file.

If the internet access information is provided through the internetlocation descriptor, the available_on_internet field may be omitted fromthe NRT-IT of FIG. 14 and FIG. 15.

FIG. 16 and FIG. 17 respectively illustrate an exemplary FDT XML(eXtensible Markup Language) schema according to the present invention.

According to FIG. 16 and FIG. 17, when an attribute is required to becommonly defined in all files declared in the FDT (or FDT instance), anFDT instance level is defined, and when an attribute is required to beindependently defined in each file, an FDT file level is defined.

Referring to FIG. 16 and FIG. 17, the portion marked as number 1corresponds to a declaration of a content linkage in an FDT instancelevel. The content linkage declared herein is given to all filesdeclared in the corresponding FDT instance. Evidently, this informationmay be overridden by newly giving a content linkage from the file level.Alternatively, when a specific file belongs not only to the content (orcontent item) defined in the FDT instance level but also to anothercontent, the content linkage may be given from the file level, which isthen notified.

The portion marked as number 2 corresponds to a declaration of a contentlinkage in a file level. Herein, when the files included in the FDTinstance belong to different contents, this method is used to signal thecontent to which each file belongs.

The portion marked as number 3 corresponds to a method of notifying foreach file whether or not the corresponding file is an entry file. Morespecifically, among the plurality of files configuring the content, afile corresponding to a root file, which must be reproduced first, orwhich must be executed first in order to access the content, is referredto as an entry file. Herein, an entry attribute may be omitted, and whenthe default value is set to ‘false’ and is omitted, this indicates thatthe corresponding file is not an entry file.

As described above, by signaling each entry status in the file leveldepending upon the group to which the corresponding file belongs, aspecific file may perform an entry function in a specific group and maynot perform any entry function in other groups.

Also, in the file level marked as number 2, one file element providesadditional information by using one or more attributes. Referring toFIG. 16 and FIG. 17, one file element uses Content-Location, TOI,Content-Length, Transfer-Length, Content-Type, Content-Encoding,Content-MD5, FEC-OTI-FEC-Encoding-ID, FEC-OTI-FEC-Instance-ID,FEC-OTI-Maximum-Source-Block-Length, FEC-OTI-Encoding-Symbol-Length,FEC-OTI-Max-Number-of-Encoding-Symbols attributes, so as to providelocation information, TOI, length information, type information,encoding information, etc., on the corresponding file.

When the file element of FIG. 16 and FIG. 17 corresponds to a filebelonging to a content available on the internet, the present inventionincludes the internet address in the Content-Location attribute valuemarked as number 4. For example, the Content-Location attribute withinthe FLUTE FDT corresponding to each file belonging to the content itemindicates the internet URL of the corresponding file. More specifically,in this case, the Content-Location attribute limits the type of the fileto ‘Internet URL’.

Meanwhile, the broadcast receiver may use the NST and the NRT-IT toprovide the user with an NRT-specific service guide screen.

At this point, the service guide screen for NRT services may be providedby using diverse methods. For example, an RT service and an NRT servicemay be simultaneously displayed in a single service guide screen, or anRT service and an NRT service may be independently displayed.

Furthermore, the RT-specific service guide screen may be shifted to theNRT-specific service guide screen, or the NRT-specific service guidescreen may be shifted to the RT-specific service guide screen.

First Embodiment

FIG. 18 illustrates an exemplary RT-specific service guide screenaccording to a first embodiment of the present invention. TheRT-specific service guide screen is configured based upon an eventinformation table (EIT) including schedule information of each event. InFIG. 18, the title of a program that is currently served through acurrent RT based upon a current time, or the title of a program that isto be serviced through an RT in a future process is displayed for eachbroadcast station.

At this point, when the user uses an input means, such as a remotecontroller, a keyboard, a mouse, a touch pad, and so on, to shift (ormove) a cursor (or high-light) at a time position preceding the currenttime, i.e., when the cursor (or high-light) is moved leftwards, whichindicates the past, the NRT-specific service guide screen is displayed.More specifically, an EPG for the RT service is shifted to an EPG forthe NRT service. For example, when it is assumed that the current timeis 6:00 P.M., and when the user uses the input means to move the cursor(or high-light) to a time position earlier than 6:00 P.M., theNRT-specific service guide screen is displayed. In other words, forexample, programs that were broadcasted earlier (or in the past) aredisplayed on the NRT-specific service guide screen.

FIG. 19 illustrates an exemplary NRT-specific service guide screenaccording to an embodiment of the present invention. More specifically,FIG. 19 illustrates an example of a service guide screen configured byarranging NRT services with programs that were broadcasted earlier (orin the past) through terrestrial networks. Herein, time information isdisplayed on the NRT-specific service guide screen. And, at this point,the time information indicates when (e.g., how many hours earlier) aspecific program was actually broadcasted based upon the current time.

FIG. 20 illustrates exemplary NRT-specific service guide screenaccording to another embodiment of the present invention. Morespecifically, FIG. 20 illustrates an example of a service guide screenconfigured by arranging NRT services with programs that were broadcastedearlier (or in the past) through terrestrial networks. Herein, also,time information is displayed on the NRT-specific service guide screen.And, at this point, the time information indicates the actual time atwhich the corresponding program was broadcasted.

However, since the programs arranged as NRT services correspond toprograms that were broadcasted earlier (or in the past) (i.e., re-runs)and are displayed based upon the time information, in this case a linkinformation connecting the RT service and the NRT service is required.For this, the present invention may include an NRT service identifierand a content identifier in a PSI/PSIP table, e.g., an EIT, or thepresent invention may include a source identifier and an eventidentifier of an EIT in an NRT service signaling channel, e.g., anNRT-IT. Alternatively, a separate table may be defined, and a linkinformation for connecting the RT service and the NRT service may bedescribed in the separately defined table. At this point, according toan embodiment of the present invention, the link information is signaledby further including a descriptor in the EIT or the NRT-IT. Also, whensignaling the link information to the NRT-IT, a flag field identifyingwhether or not the corresponding program is a re-run may be furtherincluded.

FIG. 21 illustrates an exemplary NRT-specific service guide screenaccording to yet another embodiment of the present invention, whereinthe time information is not displayed on the NRT-specific service guidescreen.

More specifically, FIG. 21 illustrates an example of a service guidescreen configured by arranging NRT services with programs that werebroadcasted earlier (or in the past) through terrestrial networks. Atthis point, according to an embodiment of the present invention, theprograms being arranged as NRT services are grouped to one or morecategories, thereby being displayed. For example, each program may bedifferentiated (sorted, aligned) by genre, as shown in FIG. 21, so as todisplay the NRT-specific service guide screen. Herein, according to anembodiment of the present invention, the genre information of eachprogram is provided through a genre descriptor included in the servicelevel of the NST or the content level of the NRT-IT. Furthermore, sinceit is assumed in the NRT-specific service guide screen that each programis a previous (or past) program, the actual broadcasting time of eachprogram may also be displayed. Herein, a downloadable time for eachprogram may also be displayed.

Herein, in the NRT-specific service guide screen, as shown in FIG. 19 orFIG. 21, when the user uses an input means, such as a remote controller,a keyboard, a mouse, a touch pad, and so on, to select a specificprogram, a sub-menu (or a sub pop-up window) enabling the user to select“Play Now” or “Schedule Advance Recording” in accordance with theattributes of the respective program, is displayed. Each of FIG. 19 toFIG. 21 shows an example of a sub-menu screen enabling the user toselect at least one of “Play Now” and “Schedule Advance Recording”, whenthe user selects a program entitled “Heroes Episode 5”.

Also, when additional information related to the selected program isserved via NRT, an additional information button may be displayed on thesub-menu screen in the form of a text or icon, so as to allow the userto recognize the presence of the additional information and select thecorresponding information. At this point, when the additionalinformation button is selected, the corresponding additional informationis provided to the user. The additional information corresponds topreviews (or recaps or trailers), View video (or watch full episodes),music video, original sound track (OST) related to the program.

When several additional information related to the program exist, anadditional information list may be displayed, so as to provide aspecific additional information selected from the additional informationlist to the user. The sub-menu screen displayed in the NRT-specificservice guide screen of FIG. 19 to FIG. 21 is a mere example given tofacilitate the understanding of the present invention. And, since theconfiguration of the sub-menu screen may be easily modified by anyoneskilled in the art, the present invention will not be limited only tothe examples given herein.

At this point, according to an embodiment of the present invention, evenif the program available for “Play Now” and the program available for“Schedule Advance Recording” correspond to the same program, if theresolution of the two programs is different, the resolution informationof each program is indicated next to each program by using a text formator an icon, thereby enabling the user to recognize the difference inresolution and to select the preference program. According to anotherembodiment of the present invention, in case of a program that isneither available for “Play Now” nor for “Schedule Advance Recording”,even if a cursor (or high-light) is placed on the corresponding programwithin the service guide screen, the corresponding program isinactivated, so that the user cannot select the corresponding program.More specifically, even if the corresponding program is selected, arelated sub-menu is not displayed. However, if at least one of “PlayNow” and “Schedule Advance Recording” is available, then the relatedsub-menu is displayed.

Meanwhile, when the user selects the “Play Now” item from the sub-menuscreen from any one of the NRT-specific service guide screens shown inFIG. 19 to FIG. 21, the corresponding program may be pre-stored in thestorage medium (e.g., HDD, flash memory) of the respective broadcastsignal or may be directly provided from the internet.

If the program available for “Play Now” is a program being provided froma web server through an internet access, the internet access informationof the program (or NRT service or content) may be acquired through theabove-described internet location descriptor, or may be acquired throughcontent-location attributes of the corresponding files of the FLUTE FDT,which belongs to the content corresponding to the program.

Furthermore, when the user selects the “Schedule Advance Recording”item, the files that belong to the content respective to the selectedprogram are downloaded through the FLUTE session at a predeterminedtime, so as to be stored in the storage medium of the respectivebroadcast receiver. Thereafter, the stored files are immediatelyoutputted or outputted upon the user's request to an output device, soas to be displayed. Then, once the downloading of the program iscompleted, an identification information that can identify thecompletion of the downloading process may be marked in a portion of theRT service screen or marked on the corresponding program within theNRT-specific service guide screen in the form of a text or icon, therebynotifying the user that the downloading process is completed.

Meanwhile, in some occasions, the program downloaded via “Play Now” orthe program downloaded via “Schedule Advance Recording” may not beplayed-back by the broadcast receiver. In this case, playback may not beperformed for many reasons. One of the reasons corresponds to when acodec for decoding the program does not exist in the broadcast receiver.The presence of a codec for decoding the corresponding program in thebroadcast receiver may be known by using at least one of the encodinginformation and the decoding parameter, which are received in a MIMEtype text form through the NST or NRT-IT. The encoding information mayinclude codec information used in the video stream of the correspondingprogram, codec information used in the audio stream of the correspondingprogram, and so on. Also, the MIME type encoding information may beprovided by being inserted in the NST or NRT-IT in a field format, ormay be provided by being inserted in a descriptor format. For example,it is assumed that a text indicating “The video codec used in Program Ais A2” is included in the encoding information as a MIME type. However,if the video codec A2 is not installed in the broadcast receiver, thebroadcast receiver is incapable of playing-back the correspondingprogram. At this point, it is also assumed that neither the video codecA2 nor any other backward compatible codec is installed.

At this point, according to an embodiment of the present invention,since playback cannot be performed even if the program is downloaded, amessage is displayed so as to allow to user to acknowledge thesituation. Herein, according to an embodiment of the present invention,the message is displayed in the form of a pop-up window.

For example, it is assumed that a download schedule is reserved in thesub-menu screen and that a video codec for the program scheduled fordownloading is not installed in the respective broadcast receiver. Inthis case, based upon the transmitted MIME-type encoding information anddecoding parameter, the broadcast receiver may generate a message saying“The video codec required for decoding Program A does not exist in thisbroadcast receiver.” or “The video codec required for decoding Program Adoes not exist in this broadcast receiver. Do you wish to download therequired video codec?” or “The video codec required for decoding ProgramA is A2.”

The message is then displayed in the form of a pop-up window. Suchmessage may also be applied when the playback option of a downloadedprogram is selected.

FIG. 22 and FIG. 23 illustrate examples of a message that can bedisplayed in the form of a pop-up window, when playback cannot beperformed due to the absence of a codec required playing-back adownloaded program in the broadcast receiver. According to an embodimentof the present invention, the message is created based upon the encodinginformation and decoding parameter, which are displayed as a MIME-typetext.

In the example shown in FIG. 22, the broadcast receiver displays amessage saying “Due to the absence of the video codec, Program A cannotbe played.” This message allows the user to recognize the reason why thecorresponding program cannot be played (or played-back).

In the example shown in FIG. 23, the broadcast receiver displays amessage saying “Due to the absence of the video codec, Program A cannotbe played. Do you wish to download the required video codec?” Herein,buttons indicating “Yes” and “No” are also displayed so as to enable theuser to select download. When the user selects the button saying “Yes”,then the required video codec is downloaded. The video codec may beprovided through an NRT service or may be provided from a web serverthrough the internet.

At this point, the downloaded video codec may be automatically installedin the respective broadcast receiver, or may be installed upon theuser's request.

Second Embodiment

FIG. 24 illustrates an exemplary RT-specific service guide screenaccording to a second embodiment of the present invention. TheRT-specific service guide screen is configured based upon an eventinformation table (EIT) including schedule information of each event.According to the second embodiment of the present invention, a buttonthat allows the screen to shift to an NRT-specific service guide screenis added in a portion of the RT-specific service guide screen of FIG.24. Herein, when this button is selected (clicked), the screen may beshifted to the NRT-specific service guide screen. In the description ofthe present invention, the button that allows the screen to shift to theNRT-specific service guide screen will be referred to as a “Viewprevious program” button, for simplicity. In the example shown in FIG.24, the “View previous program” button is added on the upper right endportion of the RT-specific service guide screen.

More specifically, when the user selects the “View previous program”button from the RT-specific service guide screen, shown in FIG. 24, anyone of the NRT-specific service guide screens shown in FIG. 25 to FIG.27 is displayed. At this point, according to an embodiment of thepresent invention, a “View current program” button is added in theNRT-specific service guide screen, so as to allow the user to return tothe current program. In each of the examples shown in FIG. 25 to FIG.27, the “View current program” button is added on the upper right endportion of the NRT-specific service guide screen. Herein, also, theprograms that were broadcasted earlier (or in the past) are displayed inthe NRT-specific service guide screen based upon time or a specificcategory.

The difference between the RT-specific service guide screen of FIG. 24and the RT-specific service guide screen of FIG. 18 is that a “View pastprogram” button is further included in the RT-specific service guidescreen of FIG. 24.

Furthermore, a difference between the NRT-specific service guide screenof FIG. 25 to FIG. 27 and the NRT-specific service guide screen of FIG.19 to FIG. 21 is that a “View current program” button is furtherincluded in the NRT-specific service guide screen of FIG. 25 to FIG. 27.For example, while displaying the NRT-specific service guide screen,when the user wishes to view the current program, the user simply needsto select the “View current program” button. Then, the NRT-specificservice guide screen shifts to the RT-specific service guide screen.Conversely, in the example shown in FIG. 19 to FIG. 21, in order to viewthe current program from the NRT-specific service guide screen, thecursor (or high-light) should be moved rightwards, which indicates thefuture. Accordingly, the RT-specific service guide screen is displayed.For example, when it is assumed that the current time is 6:00 P.M., andwhen the user uses the input means to move the cursor (or high-light) toa time position later than 6:00 P.M., the RT-specific service guidescreen is displayed.

Similarly, in the NRT-specific service guide screen of FIG. 25 and FIG.26, since the programs arranged as NRT services correspond to programsthat were broadcasted earlier (or in the past) and are displayed basedupon the time information, in this case also a link informationconnecting the RT service and the NRT service is required. For this, thepresent invention may include an NRT service identifier and a contentidentifier in a PSI/PSIP table, e.g., an EIT, or the present inventionmay include a source identifier and an event identifier of an EIT in anNRT service signaling channel, e.g., an NRT-IT. Alternatively, aseparate table may be defined, and a link information for connecting theRT service and the NRT service may be described in the separatelydefined table. At this point, according to an embodiment of the presentinvention, the link information is signaled by further including adescriptor in the EIT or the NRT-IT. Also, when signaling the linkinformation to the NRT-IT, a flag field identifying whether or not thecorresponding program is a re-run (i.e., past program) may be furtherincluded.

Also, the sub-menu screen displayed in the NRT-specific service guidescreen of FIG. 25 to FIG. 27 is a mere example given to facilitate theunderstanding of the present invention. And, since the configuration ofthe sub-menu screen may be easily modified by anyone skilled in the art,the present invention will not be limited only to the examples givenherein.

Furthermore, according to an embodiment of the present invention, in theNRT-specific service guide screen of FIG. 25 to FIG. 27, even if theprogram available for “Play Now” and the program available for “ScheduleAdvance Recording” correspond to the same program, if the resolution ofthe two programs is different, the resolution information of eachprogram is indicated next to each program by using a text format or anicon, thereby enabling the user to recognize the difference inresolution and to select the preference program.

For the non-described parts of FIG. 24 to FIG. 27, details described inFIG. 18 to FIG. 21 may be directly applied. For example, if the programavailable for “Play Now” is a program being provided from a web serverthrough an internet access, the internet access information of theprogram (or NRT service or content) may be acquired through theabove-described internet location descriptor, or may be acquired throughcontent-location attributes of the corresponding files of the FLUTE FDT,which belongs to the content corresponding to the program.

In another example, when a codec that is to be applied to a program,which is to be downloaded through the internet or in NRT, or to aprogram that is already downloaded, a message is created by referring tothe encoding information and decoding parameter transmitted as the MIMEtype, so as to be displayed. In the example shown in FIG. 22, thebroadcast receiver displays a message saying “Due to the absence of thevideo codec, Program A cannot be played.” This message allows the userto recognize the reason why the corresponding program cannot be played(or played-back). And, in the example shown in FIG. 23, the broadcastreceiver displays a message saying “Due to the absence of the videocodec, Program A cannot be played. Do you wish to download the requiredvideo codec?” Herein, buttons indicating “Yes” and “No” are alsodisplayed so as to enable the user to select download. When the userselects the button saying “Yes”, then the required video codec isdownloaded. The video codec may be provided through an NRT service ormay be provided from a web server through the internet. At this point,the downloaded video codec may be automatically installed in therespective broadcast receiver, or may be installed upon the user'srequest.

Third Embodiment

(a) of FIG. 28 illustrates an exemplary RT-specific service guide screenaccording to a third embodiment of the present invention, and (b) ofFIG. 28 illustrates an exemplary display screen being shifted from theRT-specific service guide screen to the NRT-specific service guidescreen, when a specific program is selected.

More specifically, according to the third embodiment of the presentinvention, an NRT-specific service guide screen subordinate to real-timebroadcast programs is provided to the user. When the user selects aspecific program from the RT-specific service guide screen, detailedinformation on the selected program is displayed as shown in (b) of FIG.28. For example, when the program ‘Boys over Flowers’ is selected fromthe RT-specific service guide screen shown in (a) of FIG. 28, thedetailed information on the selected program is displayed as shown in(b) of FIG. 28.

At this time, when additional information associated with the selectedprogram is serviced in NRT, information indicating the existence ofadditional information is displayed in the form of a text or icon. Theadditional information may correspond to previews (or recaps), viewvideo (or watch full episodes), music video, original sound track (OST)related to the program.

For example, in case the additional information ‘View video’ is providedthrough an NRT service, a button saying ‘View video’ is displayed at aportion of the detailed information screen. Then, a list of programsthat can be viewed through ‘View video’ is displayed at a portion of thedetailed information screen. At this point, the list of programs may bedisplayed automatically, or may be displayed only when the user selectsthe ‘View video’ button. The additionally, information may be providedthrough the internet, or may be provided through a FLUTE session innon-real time.

If 2 or more sets of additional information related to the selectedprogram exist (e.g., View Video, Preview, Viewers' Opinion Board, etc.),a list of additional information is first displayed, thereby enablingthe user to select one of the wanted additional information.

(b) of FIG. 28 illustrates an example of a display screen when a Viewvideo program of a program entitled ‘Boys over Flowers’ is being servedin NRT, wherein a ‘View Video’ button is displayed at the upper portionof the detailed information screen of ‘Boys over Flowers’, and wherein alist of episodes of the program ‘Boys over Flowers’ (or program titles)that were broadcasted in the past (or earlier) is displayed at the lowerportion of the detailed information screen. Herein, the list of programtitles that were broadcasted in the past may all be displayed, or onlythe list of recently broadcasted program titles may be displayed.

At this point, when the user uses an input means, such as a remotecontroller, a keyboard, a mouse, a touch pad, and so on, to select aspecific program from the View video program list, the selected programmay be executed (or activated) immediately, or a sub-menu (or a subpop-up window) enabling the user to select “Play Now” or “ScheduleAdvance Recording” in accordance with the attributes of the respectiveprogram may be displayed.

In this case also, even if the program available for “Play Now” and theprogram available for “Schedule Advance Recording” correspond to thesame program, if the resolution of the two programs is different, theresolution information of each program is indicated next to each programby using a text format or an icon, thereby enabling the user torecognize the difference in resolution and to select the preferenceprogram.

Furthermore, according to an embodiment of the present invention, incase a program that is neither available for “Play Now” nor for“Schedule Advance Recording” exists in the View video program list, thecorresponding program may become inactive, thereby preventing the userfrom selecting the corresponding program. However, if the program isavailable for at least one of “Play Now” and “Schedule AdvanceRecording”, then the sub-menu screen is displayed. And, in case aprogram that is available for “Play Now” within the View video programlist, the corresponding program may be pre-stored in the storage medium(e.g., HDD, flash memory) of the respective broadcast signal or may bedirectly provided from the internet. If the program available for “PlayNow” is a program being provided from a web server through an internetaccess, the internet access information of the program (or NRT serviceor content) may be acquired through the above-described internetlocation descriptor, or may be acquired through content-locationattributes of the corresponding files of the FLUTE FDT, which belongs tothe content corresponding to the program.

Furthermore, when a codec that is to be applied to a program, which isto be downloaded through the internet or in NRT, or to a program that isalready downloaded, a message is created by referring to the encodinginformation and decoding parameter transmitted as the MIME type, so asto be displayed. In the example shown in FIG. 22, the broadcast receiverdisplays a message saying “Due to the absence of the video codec,Program A cannot be played.” This message allows the user to recognizethe reason why the corresponding program cannot be played (orplayed-back). And, in the example shown in FIG. 23, the broadcastreceiver displays a message saying “Due to the absence of the videocodec, Program A cannot be played. Do you wish to download the requiredvideo codec?” Herein, buttons indicating “Yes” and “No” are alsodisplayed so as to enable the user to select download. When the userselects the button saying “Yes”, then the required video codec isdownloaded. The video codec may be provided through an NRT service ormay be provided from a web server through the internet. At this point,the downloaded video codec may be automatically installed in therespective broadcast receiver, or may be installed upon the user'srequest.

Also, according to an embodiment of the present invention, when a ‘Back’button is selected from the detailed information screen shown in (b) ofFIG. 28, the display screen may return to the RT-specific service guidescreen shown in (a) of FIG. 28.

Fourth Embodiment

(a) of FIG. 29 illustrates an exemplary RT-specific service guide screenaccording to a fourth embodiment of the present invention, and (b) ofFIG. 29 illustrates an exemplary detailed information screen of aselected program. Herein, when additional information being provided inNRT exists, a text or icon enabling the user to recognize the existenceof such additional information is displayed next to the correspondingprogram in the RT-specific service guide screen. In (a) of FIG. 29, anicon is used to indicate the existence (or presence) of the additionalinformation. The additional information corresponds to previews (orrecaps), View video (or watch full episodes), music video, originalsound track (OST) related to the program. The additional information mayalso be available on the internet (or provided through the internet).

At this point, when the user selects an icon indicating the existence ofthe additional information, or when the user selects the title of thecorresponding program, from the RT-specific service guide screen shownin (a) of FIG. 29, a detailed information screen is displayed as shownin (b) of FIG. 29. If only one set of information is provided for theselected program, an execution button is displayed at the lower portionof the detailed information screen. Herein, the execution buttonincludes information indicating what the additional informationcorresponds to. In the example shown in (b) of FIG. 29, when a previewof a program entitled ‘Boys over Flowers’ is available through an NRTservice or on the internet, an execution button saying “Video Preview”is displayed on the detailed information screen.

At this point, when the user clicks on this button, a preview video of‘Boys over Flowers’ is played.

If one or more sets of additional information are provided for theprogram entitled ‘Boys over Flowers’, an execution button for each setof additional information may be displayed. For example, when it isassumed that a preview and a music video related to the program entitled‘Boys over Flowers’ is provided through an NRT service or the internet,a “Video Preview” execution button and a “Music Video” execution buttonmay be displayed. And, when the “Music Video” execution button isselected, a music video of ‘Boys over Flowers’ is played. According toanother embodiment of the present invention, after displaying a list ofadditional information, the specific additional information selectedfrom the list may be executed.

Furthermore, if the additional information has not yet been downloaded,a sub-menu (or button) enabling the user to select “Schedule Download”may be additionally displayed. According to another embodiment of thepresent invention, for additional information that requires a codec,when a codec that is required for decoding the corresponding additionalinformation does not exist in the broadcast receiver, the broadcastreceiver may display a message notifying the user of the absence of suchcodec. Thus, the user may refer to this message prior to selecting“Schedule Download” or “Play” functions.

In the above description, a method of shifting from an RT-specificservice guide screen to an NRT-specific service guide screen, or amethod of shifting from an NRT-specific service guide screen to anRT-specific service guide screen, a method of providing NRT-specificservice guide subordinate to real-time broadcasting, a method ofidentifying programs providing additional information by using icons,and so on have been described in detail based upon a fixed NRT service.

However, it is apparent that this method can be applied to a mobile NRTservice. More specifically, a signaling information table for the mobileNRT service according to the present invention include a service maptable (SMT). More specifically, a signaling information table for amobile NRT service according to the present invention includes a servicemap table (SMT). Also, an OMA BOAST service guide is used to providecontent detailed information. The SMT is in correspondence with the NSTof the fixed NRT service, and the OMA BOAST service guide is incorrespondence with the NRT-IT of the fixed NRT service.

The SMT provides real-time services or non-real time services includedin the mobile broadcast program and received and also provides accessinformation of the component (or component item) included in eachservice. More specifically, by using the SMT and the OMA BOAST serviceguide, the list of recordings of the NRT contents stored in the storagemedium may be created and displayed on the display screen. Sincereference may be made to the fixed NRT service for the method ofmanaging a storage medium and a method of displaying a list ofrecordings in the mobile NRT service, detailed description of the samewill be omitted for simplicity.

FIG. 30 illustrates a block view showing a structure of a broadcastreceiver for fixed NRT services according to an embodiment of thepresent invention.

The broadcast receiver in FIG. 30 includes an Operation Controller 100,a Baseband processor 110, a Service Demultiplexer 120, a Streamcomponent handler 130, a Media Handler 140, a File Handler 150, aService Manager 160, a PVR Manager 170, a first storage unit 180, an SGHandler 190, an EPG Manager 200, an NRT Service Manager 210, anApplication Manager 220, a MiddleWare Engine 230, a Presentation Manager240, a UI Manager 250, and an internet network interface (260).

The Baseband processor 110 includes a Tuner 111 and a Demodulator 112.The Service Demultiplexer 120 includes an MPEG-2 TP Handler 121, aPSI/PSIP Handler 122, a Demultiplexer 123, a Descrambler 124 and asecond storage unit 125.

The Stream component handler 130 includes a Packetized Elementary Stream(PES) decoder 131, an Elementary Stream (ES) decoder 132, a PCR Handler133, an STC Handler 134, a DSM-CC Addressable Section Handler 135, an IPDatagram Handler 136, a Descrambler 137, a UDP Handler 138, a ServiceSignaling Section Handler 138-1, and a Conditional Access System (CAS)139.

The Media Handler 140 includes an A/V Decoders 141. The File Handler 150includes an ALC/LCT Stream Handler 151, a File Reconstruction Buffer152, an XML Parser 153, an FDT Handler 154, a Decompressor 155, a thirdstorage unit 156, and a File Decoder 157.

The Tuner 111 for example in FIG. 30 detects signal transmitted over theterrestrial system with the control from the Service Manager 160 andtunes only the wanted channel, down converts to Intermediate Frequency(IF), and outputs to the Demodulator 112. The Tuner 111 may receive bothreal time stream and non-real time stream. In the present invention,non-real time stream is referred to as NRT stream.

The Demodulator 112 receives digital IF signal of pass bandwidthinputted from the Tuner 111 and performs automatic gain control,reconstructs carrier frequencies and timing to convert into basebandsignal and equalizes the channel. For example, if the broadcast signalis a VSB modulated signal, a VSB demodulation process is executed forautomatic gain control, and reconstructs carrier frequencies and timing.In the Demodulator 112, demodulated and equalized channel data isoutputted to the MPEG-2 TP Handler 121 in a MPEG-2 Transport Stream (TS)packet format.

The MPEG-2 TP Handler 121 is configured of an MPEG-2 TP Buffer and anMPEG-2 TP Parser, temporarily stores the Demodulator 112 output and thenanalyzes TS Header, and outputs to the Demultiplexer 123 if theDemodulator 112 output is a real time A/V TS packet or NRT TS packet andoutputs to the PSI/PSIP Handler 122 if the output is a TS packet forPSI/PSIP table.

The PSI/PSIP Handler 122 is configured of a PSI/PSIP Section Buffer anda PSI/PSIP Parser, and temporarily stores the outputted TS packet fromthe MPEG-2 TP Handler 121 to reconstruct the corresponding table fromPSI/PSIP Section data included in the payload of TS packet withreferencing table identifier and then parse it. At this time, it ispossible to find out whether one table is configured by one section orplurality of sections by the table_id field, section_number field, andlast_section_number field within the corresponding section. Further,completing the corresponding table is possible by gathering sectionshaving identical table identifiers. For example, it is possible tocomplete a VCT by gathering the sections having table identifiersallocated to VCT. Also, each of the parsed table information iscollected by the Service Manager 160 and then stored in the firststorage unit 180. The VCT, PAT, PMT, DST, EIT, ETT and the like, arestored in the first storage unit 180 after going through the process.The Service Manager 160 stores the table information in the firststorage unit 180 in the Service Map & Guide DB format.

The Demultiplexer 123 divides audio TS packet and video TS packet andthen outputs to the PES Decoder 131 if the TS packet is real time A/V TSpacket and outputs to the DSM-CC Handler 135 if it is an NRT TS packet.Also, the Demultiplexer 123 outputs to the PCR Handler 133 if the TSpacket includes Program Clock Reference (PCR) and outputs to the CAS 139if the TS packet includes Conditional Access (CA) information. The NRTTS packet is divided into TS packet including NRT service data and TSpacket including NRT service signaling channel. A unique PID isallocated to identify the NRT service in the TS packet of the NRTservice data and the PID of the TS packet including the NRT servicesignaling channel is extracted using DST and PMT.

The Demultiplexer 123 outputs to the Descrambler 124 if the payload ofthe inputted TS packet is scrambled and the Descrambler 124 receivesdescrambling information needed for descrambling (for example, controlword used in scrambling) from the CAS 139 and performs descrambling ofthe TS packet.

The Demultiplexer 123 stores A/V packet of real time from any one of therecord, timed-record, or time shift request in the second storage unit125. The second storage unit 125 is a mass storage device, an example ofit can be a HDD. The download (storage) and upload (playing) in thesecond storage unit 125 is controlled by the PVR Manager 170 or theService manager 160.

In accordance with a playback request, the demultiplexer 123 separatesan audio TS packet and a video TS packet from an A/V TS packet uploadedfrom the second storage unit 125, thereby outputting the separated TSpackets to a PES decoder 131.

The Demultiplexer 123, in order to perform such functions, is controlledby Service Manager 160 and/or PVR Manager 170.

Thus the Service Manager 160 receives DST by extracting the PID of theDST from the service location descriptor (or ES loop of PMT) of the VCTwhen the service_type field value indicates that NRT service istransmitted.

Further, NRT service is identified through the received DST, andextracts DST and PMT by using the PID of MPEG-2 TS including NRT servicesignaling channel. The extracted PID is outputted to the Demultiplexer123. The Demultiplexer 123 outputs to the Addressable Section Handler135 the MPEG-2 TS packets corresponding to PID outputted by the ServiceManager 160.

The PCR is a standard time value used in syncing audio ES and video ESin the A/V Decoder 141. The PCR Handler 133 outputs to STC Handler 134reconstructed PCR included in the payload of the inputted TS packet. TheSTC Handler 134 outputs to the A/V Decoder 141 reconstructed System TimeClock (STC) which is the standard clock from the system by the PCR.

The PES Decoder 131 is configured with a PES Buffer and a PES Handler,temporarily stores audio TS packet and video TS packet and removes TSheader from each TS packet and reconstructs to audio PES and video PES.The reconstructed audio PES and video PES is outputted to the ES Decoder132. The ES Decoder 132 is configured with an ES Buffer and an ESHandler, removes each PES header from audio PES and video PES andreconstructs audio ES and video ES which are pure data.

The A/V Decoder 141 uses each decoding algorithms to decode the audio ESand video ES and reconstructs to pre-compressed status and then outputsto the Presentation Manager 240. At this point, depending on the STC,the time sync is executed when audio ES and video ES are decoding. Inone example, the audio decoding algorithm may apply at least one of AC-3decoding algorithm, MPEG 2 audio decoding algorithm, HE AAC decodingalgorithm, AAC SBR decoding algorithm, AAC+ decoding algorithm, HE AACdecoding algorithm, AAC SBR decoding algorithm, MPEG surround decodingalgorithm, or BSAC decoding algorithm, and the video decoding algorithmmay apply at least one of MPEG 2 video decoding algorithm, MPEG 4 videodecoding algorithm, H.264 decoding algorithm, SVC decoding algorithm,and VC-1 decoding algorithm.

The CAS 139 is configured with a CA Stream Buffer and a CA StreamHandler, and the TS packet outputted from the MPEG-2 TP Handler 121 orthe service protection data reconstructed and outputted from the UDPDatagram Handler 138 is temporarily stored and then reconstruct theneeded information (control word used in scrambling) to descramble thestored TS packet or the service protected data. Thus, the CAS 139acquires necessary information to descramble after extracting theEntitlement Management Message (EMM) and Entitlement Control Message(ECM) included in the payload of the TS packet, and then by analyzingthe extracted EMM and ECM. The ECM may include the Control Word (CW)used in scrambling. The CW may be encrypted using the authenticationkey. The EMM may include authentication key of the corresponding dataand the requirements information. The acquired information necessary fordescrambling from the CAS 139 will be outputted to the Descramblers 124,137.

The DSM-CC Section Handler 135 is configured with a DSM-CC SectionBuffer and a DSM-CC Section Parser, temporarily stores the TS packetoutputted from the Demultiplexer 123 and then reconstructs theaddressable section included in the payload of the TS packet, andoutputs to the IP Datagram Handler 136 after removing the header and theCRC checksum from the addressable section and then reconstructing the IPDatagram. The IP Datagram Handler 136 is configured with an IP DatagramBuffer and an IP Datagram Parser, and after buffering the IP datagramdelivered from the DSM-CC Section Handler 135, extracts and analyzes theheader of the buffered IP datagram and then outputs to the UDP DatagramSection Handler 138 after reconstructing the UDP datagram from thepayload of the IP datagram.

At this point, if the IP datagram is scrambled, the scrambled UDPdatagram is descrambled in the Descrambler 137 and then outputted to theUDP Datagram Handler 138. In one example, the Descrambler 137 gathersinformation needed for descrambling (for example, control words neededfor scrambling) from the CAS 139 and descrambles the UDP datagram andthen outputs to the UDP Datagram Handler 138.

The UDP Datagram Handler 138 is configured with UDP Datagram Buffer andUDP Datagram Parser, and after buffering the UDP datagram outputted fromthe IP Datagram Handler 136 or the Descrambler 137, extracts andanalyzes the header of the buffered UDP datagram and reconstructs thedata included in the payload of the UDP datagram. At this point, if thereconstructed data is service protection data then it is outputted tothe CAS 139 and if it is NRT service signaling data, then it isoutputted to the service signaling section handler 138-1, and if it isNRT service data then it is outputted to the ALC/LCT stream handler 151.

In an embodiment, the access information of the IP datagram transmittingNRT service signaling channel is a well-known destination IP address andwell-known destination UDP port number.

Therefore, the IP Datagram Handler 136 and UDP Datagram Handler 138 haswell-known destination IP multicast address and well-known destinationUDP port number, and the IP multicast stream which transmits NRT servicesignaling channel, extracts the NRT service signaling data and outputsto the Service Signaling Section Handler 138-1.

Additionally, the service signaling section handler 138-1 is configuredof a service signaling section buffer and a service signaling sectionparser. Herein, the service signaling section handler 138-1 recovers andparses NST, as shown in FIG. 10 and FIG. 11, and NRT-IT, as shown inFIG. 14 and FIG. 15, from the NRT service signaling data, therebyoutputting the processed data to a service manager 160. When the NST isparsed, access information of a FLUTE session, which transmitscontents/files configuring the NRT service, may be obtained. Theinformation parsed from the NST and the NRT-IT is collected (orgathered) by the service manager 160, thereby being stored in the firststorage unit 180. The service manager 160 stores the informationextracted from the NST and the NRT-IT in the first storage unit 180 inthe form of a service map and a service guide. According to anotherembodiment of the present invention, the function (or role) of theservice manager 160 may be performed by an NRT service manager 210. Morespecifically, the information parsed from the NST and the NRT-IT may becollected (or gathered) by the NRT service manager 210, so as to bestored in the first storage unit 180.

Furthermore, when the user requests a service guide screen through a UImanager 250, the service manager 160 or the NRT service manager 210displays an RT-specific service guide screen, as shown in FIG. 20, byusing the information stored in the first storage unit 180, based uponthe control of the operation controller 100. At this point, when theuser uses an input means, such as a remote controller, a keyboard, amouse, a touch pad, and so on, to select a “View previous program” atthe upper portion of the RT-specific service guide screen, theRT-specific service guide screen is shifted to an NRT-specific serviceguide screen, as shown in FIG. 21. Herein, in order to return to thecurrent broadcast, a “View current program” button is provided at theupper portion of the displayed NRT-specific service guide screen.

Even if the program available for “Play Now” and the program availablefor “Schedule Advance Recording” correspond to the same program, if theresolution of the two programs is different, the service manager 160 orthe NRT service manager 210 displays (or indicates) resolutioninformation of each program next to each program by using a text formator an icon, thereby enabling the user to recognize the difference inresolution and to select the preference program. At this point, if theprogram available for “Play Now” is a program being provided from a webserver through an internet access (i.e., web contents), the internetaccess information of the program may be acquired through theabove-described internet location descriptor, or may be acquired throughcontent-location attributes of the corresponding files of the FLUTE FDT,which belongs to the content corresponding to the program. Also, when acodec, which is to be applied to a program that is to be downloaded viaNRT or to a program that is already downloaded, does not exist, theservice manager 160 or the NRT service manager 210 creates a messageupon reference to the transmitted MIME-type encoding information anddecoding parameters, thereby displaying the created message.

Thereafter, a program, content, and additional information beingprovided via NRT, and which are scheduled for downloading, aredownloaded at a predetermined time through the FLUTE session. At thispoint, the downloaded program, content, and additional information passthrough a file decoder 157 so as to be stored in the third storage unit156, or the downloaded program, content, and additional information aredisplayed on the display screen through a presentation manager 240.

At this point, when the program, content, and additional information arebeing downloaded, the NRT service manager 210 may be able to notify theuser whether downloading has not begun yet, or whether downloading is inprogress, or whether downloading has been completed, by using letters,icons, colors, and so on, so that the user can be aware of thedownloading status.

The ALC/LCT Stream Handler 151 is configured with an ALC/LCT StreamBuffer and an ALC/LCT Stream Parser and after buffering the ALC/LCTstructure data outputted from the UDP Datagram Handler 138, analyzes theheader and the header extension of the ALC/LCT session buffered from thedata. After analyzing the header and the header extension of the ALC/LCTsession, if the data transmitted through ALC/LCT session is in XMLstructure then it is outputted to the XML Parser 153, and if the data isin file structure, it is temporarily stored in the File ReconstructionBuffer 152 and outputted to the File Decoder 157 or stored in the thirdstorage unit 156. If the data transmitted through ALC/LCT session isdata for NRT service, the ALC/LCT stream handler 151 gets controlled bythe NRT service manager 210. If the data transmitted through ALC/LCTsession is compressed, the Decompressor 155 decompresses and outputtedto the XML Parser 153, the File Decoder 157, or the third storage unit156.

The XML Parser 153 analyzes the XML data transmitted through ALC/LCTsession and if the analyzed data is filed-based service then it isoutputted to the FDT Handler 154 and if it is a data for service guide,then it is outputted to the SG Handler 190.

The FDT Handler 154 analyzes and processes the File Description Table ofthe FLUTE protocol through the ALC/LCT session. The FDT Handler 154 iscontrolled by the NRT Service Manager 210 if the received file is forthe NRT service.

The SG Handler 190 gathers and analyzes the data for the service guidetransmitted in XML structure, and then outputs to the EPG Manager 200.

The File Decoder 157 decodes the file outputted from the FileReconstruction Buffer 152, file outputted from the Decompressor 155, orfiled uploaded from the third storage unit 156 using the pre-selectedalgorithm and outputs to the Middleware (M/W) Engine 230 or to the A/VDecoder 141.

The M/W Engine 230 interprets and executes the application, which is thedata of the file structure. Further, through the Presentation Manager240, the application may be outputted to an output device such as ascreen or a speaker. In an embodiment, the M/W Engine 230 is a JAVAplatform based M/W Engine.

The EPG Manager 200, depending upon the input from the user, outputs theservice guide data after converting into a display format received fromthe SG Handler 190 to the Presentation Manager 240. The ApplicationManager 220 manages the handling of the application data received in afile format.

The Service Manager 160 gathers and analyzes the NRT service signalingdata transmitted through the NRT service signaling channel or thePSI/PSIP table data and creates a service map and the stores in thesecond storage unit 125. The Service Manager 160 controls the accessinformation of the NRT service that the user wants and controls theTuner 111, Demodulator 112, and the IP Datagram Handler 136.

The Operation Controller 100 according to the command from the userthrough the UI Manager 250, controls at least one of the Service Manager160, the PVR Manager 170, the EPG Manager 200, the NRT Service Manager210, the Application Manager 220, and the Presentation Manager 240, andexecutes the user's command.

The NRT Service Manager 210 manages the NRT Service transmitted incontent/file format through the FLUTE session on the IP layer.

The UI Manager 250 delivers the user's input through the UI to theOperation Controller 100.

The Presentation Manager 240 provides the user through a speaker and/ora screen at least one of the audio and video data outputted from the A/VDecoder 141, file data outputted from the M/W Engine 230, or serviceguide data outputted from the EPG Manager 210.

As described above, according to the embodiment of the presentinvention, since an RT-specific service guide screen may be easilyshifted to an NRT-specific service guide screen, or since anNRT-specific service guide screen may be easily shifted to anRT-specific service guide screen, the user may be able to convenientlyuse the NRT service and the RT service. Also, since codec information ofa specific program, content, and additional information may be indicatedbased upon encoding information transmitted as a MIME type, a waste oftime caused by downloading programs, contents, and additionalinformation that cannot be played (or played-back) may be prevented.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

1. A method of processing a non-real time service of a broadcastreceiver, comprising: receiving a signaling information table includingadditional information on contents configuring the non-real time serviceand a content identifier for each content; acquiring and storing theadditional information on contents and the content identifier for eachcontent from the signaling information table; when a non-real timespecific service guide is requested from a real-time specific serviceguide screen, configuring the non-real time specific service guide basedupon the stored additional information and content identifier of thestored contents, and displaying a non-real time specific service guidescreen; and performing a playback or download scheduling function on thecontent selected from the non-real time specific service guide screen.2. The method of claim 1, wherein, in the step of displaying thenon-real time specific service guide screen, when a high-light is movedfurther towards a left side than a current time displayed on thereal-time (RT) specific service guide screen, the RT-specific serviceguide screen is shifted to the non-real time (NRT) specific serviceguide screen.
 3. The method of claim 1, wherein the RT-specific serviceguide screen includes a menu button for viewing a previous program, andwherein the NRT-specific service guide screen includes a menu button forviewing a current program.
 4. The method of claim 3, wherein, in thestep of displaying the non-real time specific service guide screen, whenthe menu button for viewing a previous program is selected from theRT-specific service guide screen, the RT-specific service guide screenis shifted to the NRT-specific service guide screen.
 5. The method ofclaim 1, wherein the contents displayed on the NRT-specific serviceguide screen are previous (or past) broadcast programs.
 6. The method ofclaim 1, wherein, in the step of displaying the non-real time specificservice guide screen, content titles are sorted based upon an actualbroadcasting time of each content, thereby being displayed on theNRT-specific service guide screen.
 7. The method of claim 1, wherein, inthe step of displaying the non-real time specific service guide screen,content titles are sorted based upon a current time, thereby beingdisplayed on the NRT-specific service guide screen.
 8. The method ofclaim 1, wherein, in the step of displaying the non-real time specificservice guide screen, content titles are sorted by category, therebybeing displayed on the NRT-specific service guide screen.
 9. The methodof claim 1, wherein a content selected from the NRT-specific serviceguide screen is downloaded through a FLUTE session at a predeterminedtime.
 10. The method of claim 1, wherein a content selected from theNRT-specific service guide screen is downloaded from a web serverthrough the internet.
 11. The method of claim 10, wherein internetaccess information of each file belonging to the content is acquiredfrom a respective Content-Location attribute of a file delivery table(FDT) of a FLUTE.
 12. The method of claim 11, wherein the FDT includes acontent identifier identifying the content in at least one of a filelevel and an instance level.
 13. The method of claim 10, whereininternet access information of the content is acquired from thesignaling information table.
 14. A broadcast receiver, comprising: atuner receiving a signaling information table including additionalinformation on contents configuring a non-real time service and acontent identifier for each content; and a service manager acquiring andstoring the additional information on contents and the contentidentifier for each content from the signaling information table,wherein the service manager configures a non-real time specific serviceguide based upon the stored additional information and contentidentifier of the stored contents, when a non-real time specific serviceguide is requested from a real-time specific service guide screen,thereby displaying a non-real time specific service guide screen, andperforms a playback or download scheduling function on the contentselected from the non-real time specific service guide screen.
 15. Thebroadcast receiver of claim 14, wherein, when a high-light is movedfurther towards a left side than a current time displayed on thereal-time (RT) specific service guide screen, the service manager shiftsthe RT-specific service guide screen to the non-real time (NRT) specificservice guide screen.
 16. The broadcast receiver of claim 14, whereinthe RT-specific service guide screen includes a menu button for viewinga previous program, and wherein the NRT-specific service guide screenincludes a menu button for viewing a current program.
 17. The broadcastreceiver of claim 16, wherein, when the menu button for viewing aprevious program is selected from the RT-specific service guide screen,the service manager shifts the RT-specific service guide screen to theNRT-specific service guide screen.
 18. The broadcast receiver of claim14, wherein the service manager sorts content titles based upon anactual broadcasting time of each content, thereby displaying the sortedcontent titles on the NRT-specific service guide screen.
 19. Thebroadcast receiver of claim 14, wherein the service manager sortscontent titles based upon a current time, thereby displaying the sortedcontent titles on the NRT-specific service guide screen.
 20. Thebroadcast receiver of claim 14, wherein the service manager sortscontent titles by category, thereby displaying the sorted content titleson the NRT-specific service guide screen.